USDA Forest Service 

 Research Paper INT-150 

 April 1974 



FAILURE SURFACES IN INFINITE SLOPES 



Michael J. Gonsior, William S. Hartsog, 

 and Glen L. Martin 



INTERMOUNTAIN FOREST AND RANGE EXPERIMENT STATION 



Forest Service 

 U.S. Department of Agriculture 

 Ogden, Utah 84401 

 Robert W. Harris, Director 



