HECKERT, J. B. (1963). Controllership / J. Brooks Heckert And James D. Willson. The Ronald Press.
Lua i Stíl Chicago (17ú heag.)HECKERT, J. Brooks. Controllership / J. Brooks Heckert And James D. Willson. The Ronald Press, 1963.
Lua MLA (8ú heag.)HECKERT, J. Brooks. Controllership / J. Brooks Heckert And James D. Willson. The Ronald Press, 1963.
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