APA (7e ed.) Bronvermelding

Barney, G. O., Blewett, J., & Barney, K. R. (1998). Threshold 2000: Critical issues and spiritual values for a global age. Millennium Institute ; CoNexus Press.

Chicago (17e ed.) Bronvermelding

Barney, Gerald O., Jane Blewett, en Kristen R. Barney. Threshold 2000: Critical Issues and Spiritual Values for a Global Age. Arlington, VA : Grand Rapids: Millennium Institute ; CoNexus Press, 1998.

MLA (8e ed.) Bronvermelding

Barney, Gerald O., et al. Threshold 2000: Critical Issues and Spiritual Values for a Global Age. Millennium Institute ; CoNexus Press, 1998.