Explorations of Equal-Tempered Microtonality / Ivan Wyschnegradsky, Manual of Quarter-Tone Harmony, Edited by Noah Kaplan and translated by Rosalie Kaplan, Brooklyn, Underwolf, 2017. 28 pages with online audio supplement / Julia Werntz, Steps to the Sea: Ear Training and Composing in a Minute Equal Temperament, Frog Peak Music, 2014. 47 pages with online audio supplement - Hasegawa, Robert (Circuit, 2019)