F P Hadlock

Estimating fetal age using multiple parameters: a prospective evaluation in a racially mixed population.

R. Harrist, S. K. Park, R. S. Sharman, 1987, American journal of obstetrics and gynecology.

Estimating fetal age: effect of head shape on BPD.

R J Carpenter, R. Deter, S. K. Park, 1981, AJR. American journal of roentgenology.