Mahrotra, Ramesh Chandra Manak Hindi Ke Shuddh Prayog - 4th ed - New Delhi Radhakrushna Prakashan 2019 - Vol 1: 204 pgs , Vol 2: 190pgs Vol 3 :178 pgs ISBN: 978-81-7119-469-8 Dewey Class. No.: H 491.435 MAH / MAN