1. Rain erosion at subsonic and supersonic speeds: an annotated bibliography;Beltran,1962
2. Waterdrop collision with solid surfaces;Engel;N.B.S. Journal of Research,1955
3. Photographic study of the impact between water drops and a surface moving at high speed;Jenkins;Royal Aircraft Establishment of Great Britain Technical Note M.E. 275,1958
4. Mechanism of rain erosion;Engel;Wright Air Development Center TR 53–192,1953
5. The fluid flow associated with the impact of liquid drops with a solid surface;Savic;National Research Council of Canada Report MT-26,1955