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All of the characters contained in Level 1, Parts 1 and 2. Thanks to Maritova for providing this list!
Chinese 中文天地 Level 1, Second Edition, Parts 1 and 2. Written and edited by Sue-mei Wu, Yuenming Yu, Yanhui Zhang, and Weizhong Tian. Published in 2010 by Prentice Hall. ISBN: 978-0205782987 and 978-005783045.