MICHAEL, E. P. (1991). Michael E. Porter On Competition And Strategy. Harvard Business School Pess.
Lua i Stíl Chicago (17ú heag.)MICHAEL, E Porter. Michael E. Porter On Competition And Strategy. Harvard Business School Pess, 1991.
Lua MLA (8ú heag.)MICHAEL, E Porter. Michael E. Porter On Competition And Strategy. Harvard Business School Pess, 1991.
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