Hiramatsu, Yoshio. <br/><br/>
Determination of the tensile strength of rock by a compress-ion test of an irregular test piece / by Yoshio Hiramatsu a-nd Yukitoshi Oka. 

 - Kyoto, Japón : Kyoto University, Engineering Research Institute 
 - [13] p. 
 - Report; No. 133 .