张怡筠. (2007). 工作其实很简单: Manage your work easily. 河北教育出版社.
Chicago Style aipamena张怡筠. 工作其实很简单: Manage Your Work Easily. 河北教育出版社, 2007.
MLA aipamena张怡筠. 工作其实很简单: Manage Your Work Easily. 河北教育出版社, 2007.
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