APA (7e ed.) Bronvermelding

DRUCKER P. (1989). MANAGEMENT CHALLENGES FOR 21ST CENTURY. BUTTER WORTH.

Chicago (17e ed.) Bronvermelding

DRUCKER P. MANAGEMENT CHALLENGES FOR 21ST CENTURY. OXFORD: BUTTER WORTH, 1989.

MLA (9e ed.) Bronvermelding

DRUCKER P. MANAGEMENT CHALLENGES FOR 21ST CENTURY. BUTTER WORTH, 1989.