Abstracts
Résumé
Cet écrit se veut une synthèse des principales trouvailles afférentes aux études de terrain conduites annuellement de 1997 à 2006 en zones intertidales du fjord du Saguenay, et de celles situées autour de sa confluence avec l’estuaire du Saint-Laurent, dans le but de mieux comprendre les stress anthropiques auxquels est soumise la mye commune (Mya arenaria), bivalve ubiquiste de ces habitats sédimentaires. À l’aide d’une batterie variée de biomarqueurs, lesquels ont fait l’objet de mesures chez l’animal entier, certains de ses tissus ou cellules, nous avons pu mettre en évidence divers effets écotoxiques qui sont vraisemblablement imputables aux sources (urbaines, industrielles, portuaires, diffuses ou atmosphériques) de contamination chimique impactant le Saguenay. Dépendant du site et de ses caractéristiques pollutionnelles, nous avons noté des dérèglements de santé chez la mye qui incluent des effets sur son système reproducteur (divers types de perturbation endocrine associés aux substances estrogéniques, aux métaux ou aux TBT), sur son système immunitaire (stimulation ou dépression d’immunocompétence jaugée par la capacité de phagocytose d’hémocytes), ainsi que des effets cumulatifs de polluants qui se traduisent par des réponses, à la hausse ou à la baisse, de biomarqueurs de défenses (e.g., métallothionéines, CYP1A1, glutathione S-transférases), de dommages (e.g., augmentation de brins d’ADN, augmentation de l’activité de cyclo-oxygénase témoignant d’inflammation, peroxydation des lipides) et morphologiques (e.g., inhibition de croissance, baisse d’indice gonado-somatique). Nous démontrons aussi une plus grande dépense en énergie au niveau mitochondrial (transport d’électrons mitochondrial dans la gonade ou glande digestive) chez les myes de zones impactées, laquelle semble pouvoir être exacerbée en conditions de stress thermiques que laissent présager les changements climatiques à venir. Au final, ce bilan d’études de biomarqueurs confirme l’utilité du modèle bivalve Mya arenaria comme bio-indicateur de la qualité hydrique du Saguenay et il renseigne sur les divers affronts que subissent ces invertébrés dans ce milieu toujours aux prises avec des sources de contamination variées. D’autres études envisagées affineront nos connaissances au sujet des risques cumulatifs liés à la contamination chimique du fjord.
Mots clés:
- Fjord du Saguenay,
- biomarqueurs,
- Mya arenaria,
- contamination chimique,
- zone intertidale,
- effets cumulatifs,
- stress thermique
Abstract
This paper presents the major findings of annual field outings conducted from 1997 to 2006 in Saguenay Fjord intertidal areas as well as those located in proximity with the St. Lawrence River estuary. Study objectives sought to enhance our understanding of pollution pressures incurred on the soft shell clam, Mya arenaria, endemic to mud flats of these regions. By measuring the responses of a battery of biomarkers in whole animals, organs or cells, we demonstrated various adverse effects that are likely linked to chemical contamination sources (municipal, industrial, portuary, non point and atmospheric) intrinsic to the Saguenay area. Based on site and pollution features proper to each, health problems were observed in clams that included effects on their reproductive system (endocrine disruption events linked to estrogenic substances, metals or TBT), on their immune system (increase or decrease of immunocompetence assessed by phagocytic performance of hemocytes), as well as cumulative effects of pollutants, shown either by upward or downward responses of defense biomarkers ((e.g., metallothioneins, CYP1A1, glutathion S‑transferase), damage biomarkers (e.g., increase in DNA strand breaks, increase in inflammatory cyclo-oxygenase activity, lipid peroxidation) and metrics biomarkers (e.g., growth inhibition, lower gonado-somatic index). In pollution-impacted sites, clams further displayed a greater expenditure of mitochondrial energy (measured by mitochondrial electron transport in gonad or digestive gland), an energy loss that could possibly be augmented under thermic stress conditions linked to climate change. This long-term biomarker work establishes Mya arenaria as a useful bioindicator species to appraise Saguenay Fjord water quality as reflected by the diverse chemical insults to which these invertebrates are exposed in an ecosystem still struggling with multiple contamination inputs. Future studies should contribute to strengthen our knowledge related to cumulative risk issues linked to the fjord’s chemical pollution.
Keywords:
- Saguenay Fjord,
- biomarkers,
- Mya arenaria,
- chemical contamination,
- intertidal zone,
- cumulative effects,
- thermic stress
Appendices
Références bibliographiques
- ABELE, D., B. BURLANDO, A. VIARENGO et H.O. PORTNER (1998). Exposure to elevated temperatures and hydrogen peroxide elicits oxidative stress and antioxidant response in the Antarctic intertidal limpet Nacella concinna. Comp. Biochem. Physiol., 120B, 425–435.Google Scholar Search this bibliographic reference on Google Scholar
- ANTIZAR-LADISLAO, B. (2008). Environmental levels, toxicity and human exposure to tributyltin (TBT)-contaminated marine environment. A review. Environ. Intern., 34, 292–308.10.1016/j.envint.2007.09.005 Google Scholar Search this bibliographic reference on Google Scholar
- BELIAEFF, B. et T. BURGEOT, T. (2002). Integrated biomarker response: a useful tool for ecological risk assessment. Environ. Toxicol. Chem., 21, 1316-1322.Google Scholar Search this bibliographic reference on Google Scholar
- BLAISE, C., F. GAGNÉ, J. PELLERIN et P.-D. HANSEN (1999). Determination of vitellogenin-like properties in Mya arenaria hemolymph (Saguenay Fjord, Canada): a potential biomarker for endocrine disruption. Environ. Toxicol., 14, 455-465.10.1002/(SICI)1522-7278(199912)14:5<455::AID-TOX2>3.0.CO;2-8 Google Scholar Search this bibliographic reference on Google Scholar
- BLAISE, C., F. GAGNÉ, J. PELLERIN, P.-D. HANSEN et S. TROTTIER (2002a). Molluscan shellfish biomarker study of the Saguenay Fjord (Quebec, Canada) with the soft-shell clam, Mya arenaria. Environ. Toxicol., 17, 170‑186.10.1002/tox.10048 Google Scholar Search this bibliographic reference on Google Scholar
- BLAISE, C., S. TROTTIER, F. GAGNÉ, C. LALLEMENT et P.-D. HANSEN (2002b). Immunocompetence of bivalve hemocytes by a miniaturized phagocytosis assay. Environ. Toxicol., 17, 160-169.10.1002/tox.10047 Google Scholar Search this bibliographic reference on Google Scholar
- BLAISE, C. F. GAGNÉ, F. et J. PELLERIN (2003). Bivalve population status and biomarker responses in Mya arenaria clams (Saguenay Fjord, Québec, Canada). Fresenius Environ. Bull., 12, 956-960.Google Scholar Search this bibliographic reference on Google Scholar
- BLAISE, C. et F. GAGNÉ (2008). Bioassays and biomarkers, two pillars of ecotoxicology: past, present and prospective uses. Fresenius Environ. Bull., sous presse.Google Scholar Search this bibliographic reference on Google Scholar
-
Boryslawskyj, M., GARROOD, A.C. et J.T Pearson (1998). Elevation of glutathione-S-transferase activity as a stress response to organochlorine compounds, in the freshwater mussel. Sphaerium corneum. Mar. Environ. Res., 24, 101–104.Google Scholar Search this bibliographic reference on Google Scholar
- BROUSSEAU P, J. PELLERIN, Y. MORIN, D. CYR, B. BLAKLEY, H. BOERMANS et M. FOURNIER (2000). Flow cytometry as a tool to monitor the disturbance of phagocytosis in the clam Mya arenaria hemocytes following in vitro exposure to heavy metals. Toxicol., 142, 145-156.10.1016/S0300-483X(99)00165-1 Google Scholar Search this bibliographic reference on Google Scholar
- CHAU Y.K., R.J. MAGUIRE, M. BROWN, F. YANG, S.P. BATCHELOR et J.A.J. THOMPSON (1997). Occurrence of butyltin compounds in mussels in Canada. Appl. Organomet. Chem., 11, 903–912.10.1002/(SICI)1099-0739(199710/11)11:10/11<903::AID-AOC658>3.0.CO;2-C Google Scholar Search this bibliographic reference on Google Scholar
- CHÈVRE, N., F. GAGNÉ, P. GAGNON, et C. BLAISE. (2003a). Application of rough sets analysis to identify polluted aquatic sites based on a battery of biomarkers: a comparison with classical methods. Chemosphere, 51, 13‑23.10.1016/S0045-6535(02)00818-4 Google Scholar Search this bibliographic reference on Google Scholar
- CHÈVRE N, F. GAGNÉ et C. BLAISE (2003b). Development of a biomarker-based index for assessing the ecotoxic potential of aquatic sites. Biomarkers, 8, 287-298.10.1080/1354750031000120134 Google Scholar Search this bibliographic reference on Google Scholar
- COSSA D. (1990). Chemical contaminants in the St. Lawrence Estuary and Saguenay Fjord. Dans : Coastal and Estuarine Studies 36. EL-SABH, M.I. et N. SILVERBERG (Éditeurs), Springer-Verlag, NY, États-Unis, pp. 239-268.Google Scholar Search this bibliographic reference on Google Scholar
- DEPLEDGE, M.H. et M.C. FOSSI (1994). The role of biomarkers in environmental assessment (2). Invertebrates. Ecotoxicol., 3, 161-172.10.1007/BF00117081 Google Scholar Search this bibliographic reference on Google Scholar
- ERNST, W., S. WEIGELT, H. ROSENTHAL et P.-D. HANSEN (1991). Dans : Testing bioconcentration of organic chemicals with the common mussel (Mytilus edulis). Bioaccumulation in Aquatic Systems : contributions to the assessment. NAGEL, R. et R. LOSKILL (Éditeurs), Weinheim, Allemagne, VCH, pp. 99-131.Google Scholar Search this bibliographic reference on Google Scholar
- FRINGS, C.S., T.W. FENDLEY, R.T. DUNN et C.A. QUEEN (1972). Improved determination of total serum lipids by the sulfo-phospho-vanillin reaction. Clin. Chem., 18, 673–674.Google Scholar Search this bibliographic reference on Google Scholar
- FUJIMOTO, Y., S. SAKUMA, T. INOUE, E. UNO et T. FUJITA (2002). The endocrine disruptor nonylphenol preferentially blocks cyclooxygenase-1. Life Sci., 70, 2209‑2214.10.1016/S0024-3205(01)01538-7 Google Scholar Search this bibliographic reference on Google Scholar
- FORTIN, G., et M. PELLETIER (1995). Synthèse des connaissances sur les aspects physiques et chimiques de l’eau et des sédiments du Saguenay : zones d’intervention prioritaire 22 et 23. Environnement Canada, Conservation de l’Environnement, Centre Saint-Laurent, Montréal, Rapport technique, 212 p.Google Scholar Search this bibliographic reference on Google Scholar
- FOURNIER M., J. PELLERIN, Y. CLERMONT, Y. MORIN et P. BROUSSEAU (2001). Effects of in vivo exposure of Mya arenaria to organic and inorganic mercury on phagocytic activity of hemocytes. Toxicol., 161, 201-211.10.1016/S0300-483X(00)00387-5 Google Scholar Search this bibliographic reference on Google Scholar
- GAGNÉ,F., M. MARION et F. DENIZEAU (1990). Metal homeostasis and metallothionein induction in rainbow trout hepatocytes exposed to cadmium. Fund. Appl. Toxicol., 14, 429-437.Google Scholar Search this bibliographic reference on Google Scholar
- GAGNÉ,F. et C. BLAISE (1995). Genotoxicity of environmental contaminants in sediments to rainbow trout hepatocytes. Environ. Toxicol. Wat. Qual., 10, 217‑229.Google Scholar Search this bibliographic reference on Google Scholar
- GAGNÉ, F. et C. BLAISE (1998). Estrogenic properties of municipal and industrial wastewaters evaluated with a rapid and sensitive chemoluminescent in situ hybridization assay (CISH) in rainbow trout hepatocytes. Aquatic Toxicol., 44, 83-91.10.1016/S0166-445X(98)00066-6 Google Scholar Search this bibliographic reference on Google Scholar
- GAGNÉ, F., C. BLAISE, J. PELLERIN et S. GAUTHIER-CLERC (2002). Alteration of the biochemical properties of female gonads and vitellins in the clam Mya arenaria at contaminated sites in the Saguenay Fjord. Mar. Environ. Res., 53, 295-310.10.1016/S0141-1136(01)00122-2 Google Scholar Search this bibliographic reference on Google Scholar
- GAGNÉ, F., C. BLAISE, J. PELLERIN, E. PELLETIER, M. DOUVILLE, S. GAUTHIER-CLERC et L. Viglino (2003). Sex alteration in soft-shell clams (Mya arenaria) observed in an intertidal zone of the Saint-Lawrence River (Quebec, Canada). Compar. Biochem. Physiol. C, 134, 189‑198.Google Scholar Search this bibliographic reference on Google Scholar
- GAGNÉ, F. et C. BLAISE (2005). Review of biomarkers and new techniques for in situ aquatic studies with bivalves. Dans : Environmental Toxicity Testing. THOMPSON, C., K. WADHIA et A.P. Loibner (Éditeurs), A.P. Blackwell Publishers, UK., pp. 207-228.Google Scholar Search this bibliographic reference on Google Scholar
- GAGNÉ, F., C. BLAISE, C. ANDRÉ et J. PELLERIN (2006a). Implication of site quality on mitochondrial electron transport activity and its interaction with temperature in feral Mya arenaria clams from the Saguenay Fjord. Environ. Res., 103, 238-246.10.1016/j.envres.2006.05.006 Google Scholar Search this bibliographic reference on Google Scholar
- GAGNÉ, F., C. BLAISE, C. ANDRÉ, C. et M. SALAZAR (2006b). Effects of municipal wastewaters and pharmaceutical products on temperature-dependent mitochondrial electron transport activity in Elliptio complanata mussels. Comp. Biochem. Physiol., 143, 388‑393.Google Scholar Search this bibliographic reference on Google Scholar
- GAGNÉ, F., C.BLAISE, J. PELLERIN, E. PELLETIER et J. STRAND (2006c). Health status of Mya arenaria bivalves collected from contaminated sites in Canada (Saguenay Fjord, Québec, Canada) and Denmark (Odense Fjord) during their reproductive period. Ecotoxicol. Environ. Saf., 64, 348-361.10.1016/j.ecoenv.2005.04.007 Google Scholar Search this bibliographic reference on Google Scholar
- GAGNÉ, F., C. BLAISE, J. PELLERIN et C. ANDRÉ (2007). Neuroendocrine disruption in Mya arenaria clams during gametogenesis at sites under pollution stress. Mar. Environ. Res., 64, 87-107.10.1016/j.marenvres.2006.12.014 Google Scholar Search this bibliographic reference on Google Scholar
- GAGNÉ, F., C. BLAISE, J. PELLERIN, M. FOURNIER, M.J. DURAND et A. TALBOT (2008). Relationships between intertidal clam population and health status of the soft-shell clam Mya arenaria in the St. Lawrence Estuary and Saguenay Fjord (Québec, Canada). Environ. Intern., 34, 30-43.10.1016/j.envint.2007.06.010 Google Scholar Search this bibliographic reference on Google Scholar
- GAUTHIER-CLERC S, J. PELLERIN, C. BLAISE et F. GAGNÉ (2002). Delayed gametogenesis of Mya arenaria in the Saguenay fjord (Canada): a consequence of endocrine disruptors? Compar. Biochem. Physiol. C, 131C, 457-67.Google Scholar Search this bibliographic reference on Google Scholar
- GIBBS, P.E. et G.W. BRYAN (1996). TBT-induced imposex in neogastropod snails: masculinization to mass extinction. Dans : Tributyltin: Case Study of an Environmental Contaminant. DE MORA, S.J. (Éditeur.), Cambridge University Press, Cambridge, UK, Chapter 7, pp. 212‑236.10.1017/CBO9780511759772.008 Google Scholar Search this bibliographic reference on Google Scholar
- GLINSKI Z et J. JAROSZ (1997). Molluscan immune defenses. Arch. Immunol. Theor. Experim., 145, 149-155.Google Scholar Search this bibliographic reference on Google Scholar
- HAMMER, C. et E. BRAUM (1988). Quantification of age pigments (Lipofuscin). Compar. Biochem. Physiol., 90B, 7‑17.Google Scholar Search this bibliographic reference on Google Scholar
- HAHN M.E., B.L. WOODWARD, J.J. SEGEMAN et S. KENNEDY (1995). Rapid assessment of induced cytochrome P4501A (CYP1A) protein and catalytic activity in fish hepatoma cells grown in multi-well plates. Response to TCDD, TCDF, and two planar PCBs. Environ. Toxicol. Chem., 15, 582-591.Google Scholar Search this bibliographic reference on Google Scholar
- HEIDRICH, D.D., S. STECKELBROECK et D. KLINGMULLER. (2001). Inhibition of human cytochrome P450 aromatase activity by butyltins. Steroids, 66, 763–769.10.1016/S0039-128X(01)00108-8 Google Scholar Search this bibliographic reference on Google Scholar
- HEISE, K., S. PUNTARULO, H.O. PORTNER et D. ABELE (2003). Production of reactive oxygen species by isolated mitochondria of the Antarctic bivalve Laternula elliptica under heat stress. Compar. Biochem. Physiol., 134A, 79‑90.Google Scholar Search this bibliographic reference on Google Scholar
- HENDERSON, R.F., W.E. BECHTOLD, J. BOND et J.D. SUN (1989). The use of biological markers in toxicology. Critical Rev. Toxicol., 20, 65-82.10.3109/10408448909017904 Google Scholar Search this bibliographic reference on Google Scholar
- HERRIES, D.G. (1967). The simultaneous estimation of orthophosphate and carbamoylphosphate and application to the aspartate transcarbamylase reaction. Biochem. Biophys. Acta, 136, 95–98.10.1016/0304-4165(67)90324-8 Google Scholar Search this bibliographic reference on Google Scholar
- KETATA I., DENIER X., HAMZA-CHAFFAI A. et C. MINIER (2008). Endocrine-related reproductive effects in molluscs. Comp. Biochem. Physiol. C, 147, 261-270.Google Scholar Search this bibliographic reference on Google Scholar
- KING, F. et T.T. PACKARD (1975). Respiration and the activity of the respiratory electron transport system in marine zooplankton. Limnol. Oceanogr., 20, 849–854.10.4319/lo.1975.20.5.0849 Google Scholar Search this bibliographic reference on Google Scholar
- JERMYN, M.A. (1975). Increasing the sensitivity of the anthrone method for carbohydrate. Anal. Biochem., 68, 332-335.10.1016/0003-2697(75)90713-7 Google Scholar Search this bibliographic reference on Google Scholar
- MARTINEAU, D., K. LEMBERGER, A. DALLAIRE, P. LABELLE, T. LIPSCOMB, P. MICHEL et I. MIKAELIAN (2002). Cancer in wildlife, a case study: beluga from the St. Lawrence estuary, Québec, Canada Environ. Health Perspect., 110, 285–292.10.1289/ehp.02110285 Google Scholar Search this bibliographic reference on Google Scholar
- MATHIEU, M., J.P. BERGERON et A.M.A. Danet (1982). L’aspartate transcarbamoylase, indice d’activité gamétogénétique chez la moule Mytilus edulis. L. Int. J. Invertebr. Reprod., 5, 337–343.Google Scholar Search this bibliographic reference on Google Scholar
- NARBONNE J.F., M. DAUBEZE, C. CLERANDEAU et P. Garrigues (1999). Scale of classification based on biochemical markers in mussels: Application to pollution monitoring in European coasts. Biomarkers, 6, 415-424.Google Scholar Search this bibliographic reference on Google Scholar
- OLIVE, P.L. (1988). DNA precipitation assay: a rapid and simple method for detecting DNA damage in mammalian cells. Environ. Mol. Mutagen., 11, 487–495.10.1002/em.2850110409 Google Scholar Search this bibliographic reference on Google Scholar
- OLSSON, P.-E., P. KLING, C. PETTERSON et C. SILVERSAND (1995). Interaction of cadmium and oestradiol-17ß on MT and vitellogenin synthesis in rainbow trout (Oncorhynchus mykiss). Biochem. J., 307, 197-203.Google Scholar Search this bibliographic reference on Google Scholar
- ORSINGER, A., E.S. MARICHICH, V.A. MOLINA et O.A. RAMIREZ (1980). A reliable and sensitive method for the simultaneous determination of dopamine, noradrenaline, 5-hydroxytryptamine and 5-hydroxy-indol acetic acid in small brain samples. Acta Physiol., 30, 111–115.Google Scholar Search this bibliographic reference on Google Scholar
- OSADA, M., UNUMA, T. et K. Mori (1992). Purification and characterization of a yolk protein from the Scallop ovary. Nippon Suisan Gakkaishi, 58, 2283-2289.10.2331/suisan.58.2283 Google Scholar Search this bibliographic reference on Google Scholar
- PELLETIER, E., et G. CANUEL (1988). Trace metals in surface sediment of the Saguenay Fjord, Canada. Mar. Poll. Bull., 19, 336-338.10.1016/0025-326X(88)90431-6 Google Scholar Search this bibliographic reference on Google Scholar
- QUINN, B., F. GAGNÉ et C. BLAISE (2004). Oxidative metabolism activity in Hydra attenuata exposed to carbamazepine. Fresenius Environ. Bull., 13, 783-788.Google Scholar Search this bibliographic reference on Google Scholar
- SCHULTE, P. et L.F. MAZZUCKELLI (1991). Validation of biological markers for quantitative risk assessment. Environ. Health Perspect., 90, 239-246.10.2307/3430874 Google Scholar Search this bibliographic reference on Google Scholar
- SKULACHEV, V.P. (1998). Uncoupling: new approaches to an old problem of bioenergetics. Biochem. Biophys. Acta, 1363, 100–124.10.1016/S0005-2728(97)00091-1 Google Scholar Search this bibliographic reference on Google Scholar
- SUZUKI, T., A. HARA, K. YAMMAGUCHI et K. MORI (1992). Purification and immunolocalization of a vitellin-like protein from the pacific oyster Crassostrea gigas. Mar. Biol., 113, 239-245.Google Scholar Search this bibliographic reference on Google Scholar
- SZABO, G., L. KOVACS et G. TELEGDY (1983). A modified screening method for rapid simultaneous determination of dopamine, noradrenaline and serotonin in the same brain region. Acta Physiol. Hung., 61, 51–57.Google Scholar Search this bibliographic reference on Google Scholar
- SMITH, J.N. et E.M. LEVY (1990). Geochronology for polycyclic aromatic hydrocarbon contamination in sediments of the Saguenay Fjord. Environ. Sci. Technol., 24, 874-879.10.1021/es00076a013 Google Scholar Search this bibliographic reference on Google Scholar
- SAINT-LOUIS, R., C. GOBEIL et E. PELLETIER (1997). Tributyltin and its degradation products in the St. Lawrence Estuary (Canada). Environ. Technol., 18, 1209–1218.Google Scholar Search this bibliographic reference on Google Scholar
- VASSEUR, P. et C. COSSU-LEGUILLE (2003). Biomarkers and community indices as complementary tools for environmental safety. Environ. Intern., 28, 711-717.10.1016/S0160-4120(02)00116-2 Google Scholar Search this bibliographic reference on Google Scholar
- VIARENGO, A., PONZANON, E., DONDERO, F. et R. FABBRI (1997). A simple spectrophotometric method for metallothionein evaluation in marine organisms: An application to Mediterranean and Antarctic molluscs. Mar. Environ. Res., 44, 69–84.10.1016/S0141-1136(96)00103-1 Google Scholar Search this bibliographic reference on Google Scholar
- VIGLINO, L., E. PELLETIER et R. ST-LOUIS (2004). Highly persistent butyltins in northern marine sediments: a long-term threat for the Saguenay Fjord (Canada). Environ. Toxicol. Chem., 11, 2673-2681.10.1897/03-674 Google Scholar Search this bibliographic reference on Google Scholar
- WILLS, E.D. (1987). Evaluation of lipid peroxidation in lipids and biological membranes. Dans : Biochemical Toxicology: A Practical Approach. SNELL, K. et B. MULLOCK (Éditeurs), IRL Press, Washington, États-Unis, pp. 127‑150.Google Scholar Search this bibliographic reference on Google Scholar
- YIN, D. (1996). Biochemical basis of lipofuscin, ceroid, and age pigment-like fluorophores. Free Radical Biol. Medicine, 21, 871-888.10.1016/0891-5849(96)00175-X Google Scholar Search this bibliographic reference on Google Scholar
- ZHU, H., G.L. BANNEBERG, P. MOLDEAUS et H.G. SHERTZER (1994). Oxidation pathways for the intracellular probe 20,70-dichlorofluorescin. Arch. Toxicol. 68, 582–587.10.1007/s002040050118 Google Scholar Search this bibliographic reference on Google Scholar
