Spry, I. C. F. (1987). Income tax refreshers, 1987. Leo Cussen Institute.
Lua i Stíl Chicago (17ú heag.)Spry, I. C. F. Income Tax Refreshers, 1987. Melbourne: Leo Cussen Institute, 1987.
Lua MLA (8ú heag.)Spry, I. C. F. Income Tax Refreshers, 1987. Leo Cussen Institute, 1987.
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