"Understanding Pure Mathematics" by A.J. Sadler is a comprehensive textbook published by Oxford University Press. Covering a range of mathematical topics, this paperback book is designed for adult learners and university students looking to deepen their understanding of pure mathematics. With a length of 608 pages, this textbook is written in English and provides a detailed exploration of various mathematical concepts, making it a valuable resource for those seeking to enhance their knowledge in the field of mathematics.