BIGG, W. W. (1972). Practical Auditing Walter W. Bigg. HFL LTD.
Lua i Stíl Chicago (17ú heag.)BIGG, Walter W. Practical Auditing Walter W. Bigg. HFL LTD, 1972.
Lua MLA (8ú heag.)BIGG, Walter W. Practical Auditing Walter W. Bigg. HFL LTD, 1972.
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