J. Spranger, K. Benirschke, J.G. Hall, W. Lenz, R.B. Lowry, J.M. Opitz, L. Pinsky, H.G. Schwarzacher, D.W. Smith,
Errors of morphogenesis: concepts and terms. Recommendations of an international working group. The Journal of Pediatrics. ,vol. 100, pp. 160- 165 ,(1982) ,
10.1016/S0022-3476(82)80261-8