Mock, V. E. (1982). Subtraction drill for levels 1-3. David S. Lake Publishers.
Chicago Style (17th ed.) CitationMock, Valerie E. Subtraction Drill for Levels 1-3. Belmont, Calif: David S. Lake Publishers, 1982.
MLA引文Mock, Valerie E. Subtraction Drill for Levels 1-3. David S. Lake Publishers, 1982.
警告:這些引文格式不一定是100%准確.