Gilbert, P. T. (1921). The key to culture: Customs, manners and niceties of society. Geographical Pub.
Citazione stile Chigago Style (17a edizione)Gilbert, Paul Thomas. The Key to Culture: Customs, Manners and Niceties of Society. Chicago: Geographical Pub, 1921.
Citatione MLA (9a ed.)Gilbert, Paul Thomas. The Key to Culture: Customs, Manners and Niceties of Society. Geographical Pub, 1921.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.