van der Laan, Mark J. and Petersen, Maya L. "Direct Effect Models" The International Journal of Biostatistics, vol. 4, no. 1, 2008. https://doi.org/10.2202/1557-4679.1064
van der Laan, M. and Petersen, M. (2008) Direct Effect Models. The International Journal of Biostatistics, Vol. 4 (Issue 1). https://doi.org/10.2202/1557-4679.1064
van der Laan, Mark J. and Petersen, Maya L. "Direct Effect Models" The International Journal of Biostatistics 4, no. 1 (2008). https://doi.org/10.2202/1557-4679.1064