Morken, N., Vogel, I., Kallen, K., Skjærven, R., Langhoff-Roos, J., Kesmodel, U. S., & Jacobsson, B. (2008). Reference population for international comparisons and time trend surveillance of preterm delivery proportions in three countries. BioMed Central.

Morken, Nils-Halvdan, Ida Vogel, Karin Kallen, Rolv Skjærven, Jens Langhoff-Roos, Ulrik Schiøler Kesmodel, and Bo Jacobsson. Reference Population for International Comparisons and Time Trend Surveillance of Preterm Delivery Proportions in Three Countries. BioMed Central, 2008.

Morken, Nils-Halvdan, et al. Reference Population for International Comparisons and Time Trend Surveillance of Preterm Delivery Proportions in Three Countries. BioMed Central, 2008.