Duff, C. P., Duff, R. P., & Duff, W. H. (1881). Book-keeping by single and double entry: A text-book for schools, and a manual of practical instruction for business men. Harper & Brothers.
Lua i Stíl Chicago (17ú heag.)Duff, C. P., R. P. Duff, agus W. H. Duff. Book-keeping by Single and Double Entry: A Text-book for Schools, and a Manual of Practical Instruction for Business Men. New York: Harper & Brothers, 1881.
Lua MLA (8ú heag.)Duff, C. P., et al. Book-keeping by Single and Double Entry: A Text-book for Schools, and a Manual of Practical Instruction for Business Men. Harper & Brothers, 1881.
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