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The fourth volume of the most popular textbook series for college-level Chinese learners in Taiwan. Contains 14 lessons. Thanks to Hugo Lopez for providing this list!
Practical Audio-Visual Chinese 實用:視聽華語 Volume 4, Second edition. Written and compiled by the National Taiwan Normal University. Published in 2008 by Cheng Chung Book Co., Ltd. 434 pages. ISBN: 978-9570917956.