APA
van Beijsterveldt C. E. M. T., Hoekstra C., Schats R., Montgomery G. W., Willemsen G. & Boomsma D. I. (20081113). Mode of conception of twin pregnancies: willingness to reply to survey items and comparison of survey data to hospital records. : Twin research and human genetics : the official journal of the International Society for Twin Studies.
Chicago
van Beijsterveldt C E M Toos, Hoekstra Chantal, Schats Roel, Montgomery Grant W, Willemsen Gonneke and Boomsma Dorret I. 20081113. Mode of conception of twin pregnancies: willingness to reply to survey items and comparison of survey data to hospital records. : Twin research and human genetics : the official journal of the International Society for Twin Studies.
Harvard
van Beijsterveldt C. E. M. T., Hoekstra C., Schats R., Montgomery G. W., Willemsen G. and Boomsma D. I. (20081113). Mode of conception of twin pregnancies: willingness to reply to survey items and comparison of survey data to hospital records. : Twin research and human genetics : the official journal of the International Society for Twin Studies.
MLA
van Beijsterveldt C E M Toos, Hoekstra Chantal, Schats Roel, Montgomery Grant W, Willemsen Gonneke and Boomsma Dorret I. Mode of conception of twin pregnancies: willingness to reply to survey items and comparison of survey data to hospital records. : Twin research and human genetics : the official journal of the International Society for Twin Studies. 20081113.