Askerud, P. (1997). A guide to sustainable book provision. Unesco.
Cita Chicago (17th ed.)Askerud, Pernille. A Guide to Sustainable Book Provision. París: Unesco, 1997.
Cita MLA (9th ed.)Askerud, Pernille. A Guide to Sustainable Book Provision. Unesco, 1997.
Atenció: Aquestes cites poden no estar 100% correctes.