PETRUȘEL, A. 2020. Book reviews: “John R. Graef, Johnny Henderson, Abdelghani Ouahab; Topological Methods for Differential Equations and Inclusions”, CRC Press, Taylor & Francis Group, Boca Raton, FL, USA, 2019, xiv + 360 pp., ISBN 9781138332294 - CAT# K393112. Studia Universitatis Babeș-Bolyai Mathematica. 65, 1 (Mar. 2020), 161–162.