Pyle, w. W. (1970). Programmed Learning Aid For Elementary Accounting William W. Pyle. Learning Systems.
Chicago-viite (17. p.)Pyle, william W. Programmed Learning Aid For Elementary Accounting William W. Pyle. Learning Systems, 1970.
MLA-viite (8. p.)Pyle, william W. Programmed Learning Aid For Elementary Accounting William W. Pyle. Learning Systems, 1970.
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