Tower, D. B., & Tweed, B. F. (1855). Gradual lessons in grammar, or, Guide to the construction of the English language by the analysis and composition of sentences. Daniel Burgess & Co..
Chicago-referens (17:e uppl.)Tower, David B., och Benjamin F. Tweed. Gradual Lessons in Grammar, or, Guide to the Construction of the English Language by the Analysis and Composition of Sentences. New York: Daniel Burgess & Co., 1855.
MLA-referens (8:e uppl.)Tower, David B., och Benjamin F. Tweed. Gradual Lessons in Grammar, or, Guide to the Construction of the English Language by the Analysis and Composition of Sentences. Daniel Burgess & Co., 1855.
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