United nations. (2013). A Guide to the Project Management Body of Knowledge project management institute (5.). library of Congress.
Cytowanie według stylu Chicago (wyd. 17)United nations. A Guide to the Project Management Body of Knowledge Project Management Institute. 5. United States of America: library of Congress, 2013.
Cytowanie według stylu MLA (wyd. 9)United nations. A Guide to the Project Management Body of Knowledge Project Management Institute. 5. library of Congress, 2013.