APA (7e ed.) Bronvermelding

Walling, D. R. (1995). At the threshold of the millenium. Phi Delta Kappa Educational Foundation.

Chicago (17e ed.) Bronvermelding

Walling, Donovan R. At the Threshold of the Millenium. Indiana: Phi Delta Kappa Educational Foundation, 1995.

MLA (9e ed.) Bronvermelding

Walling, Donovan R. At the Threshold of the Millenium. Phi Delta Kappa Educational Foundation, 1995.