Langdon, D. B. (1951). Practice of book keeping with some opinions on its nature, status and future. Phoneniox house.
Trích dẫn kiểu ChicagoLangdon, Daviers B.N. Practice of Book Keeping with Some Opinions on Its Nature, Status and Future. London: Phoneniox house, 1951.
Trích dẫn MLALangdon, Daviers B.N. Practice of Book Keeping with Some Opinions on Its Nature, Status and Future. Phoneniox house, 1951.
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