Hahn, R. A., Wetterhall, S. F., Gay, G. A., Harshbarger, D. S., Burnett, C. A., Parrish, R. G., & Orend, R. J. (2002). The recording of demographic information on death certificates: A national survey of funeral directors. Association of Schools of Public Health.

Hahn, Robert A., Scott F. Wetterhall, George A. Gay, Dorothy S. Harshbarger, Carol A. Burnett, Roy Gibson Parrish, e Richard J. Orend. The Recording of Demographic Information On Death Certificates: A National Survey of Funeral Directors. Association of Schools of Public Health, 2002.

Hahn, Robert A., et al. The Recording of Demographic Information On Death Certificates: A National Survey of Funeral Directors. Association of Schools of Public Health, 2002.