SHEA MICHAEL. (1988). INFLUENCE: HOW TO MAKE THE SYSTEM WORK FOR YOU. SPHERE BOOKS LTD.
Chicago-viite (17. p.)SHEA MICHAEL. INFLUENCE: HOW TO MAKE THE SYSTEM WORK FOR YOU. LONDON: SPHERE BOOKS LTD, 1988.
MLA-viite (9. p.)SHEA MICHAEL. INFLUENCE: HOW TO MAKE THE SYSTEM WORK FOR YOU. SPHERE BOOKS LTD, 1988.
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