Lakhdar, C.B. 2008

Ciecierski, C.C. 2007

Kaufmann, D., Kraay, A., Mastruzzi, M. 2006

Yürekli, A.A., Sayginsoy, O. 2008

Yürekli, A.A., Zhang, P. 2000

Sung, H.Y., Hu, T.W., Keeler, T.E. 1994

Chaloupka, F.J., Saffer, H. 1992

Gallus, S., Lugo, A., La Vecchia, C. et al. 2012

Gallus, S., Tramacere, I., Zuccaro, P. et al. 2009

Guindon, G.E., Driezen, P., Chaloupka, F.J. et al. 2014