Fry, R., & Hume, G. B. (1967). Manual of Commercial Correspondence. Issac Pitman.
Dyfyniad Arddull ChicagoFry, Roland, and G Bayley Hume. Manual of Commercial Correspondence. London: Issac Pitman, 1967.
Dyfyniad MLAFry, Roland, and G Bayley Hume. Manual of Commercial Correspondence. Issac Pitman, 1967.
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