1. L'évaporation d'un bac d'eau libre—sa signification restreinte;Bultot;J. Hydrol.,1973
2. Some remarks on Penman's equations for the evapotranspiration;Businger;Neth. J. Agric. Sci.,1956
3. Natural evaporation from open water, bare soil and grass;Penman;Proc. R. Soc., Lond., Ser. A,1948
4. Some physical aspects of assimilation and transpiration;Penman;Proc. Symp. Soc. Exp. Biol.,1951
5. Over stralingsmetingen, de warmtebalans en de verdamping van gras;Scholte Ubing;Med. Landbouwhogesch.,1959