Le Bon, Gustave,  1841-1931 <br/><br/>
The evolution of forces / 
by Gustave Le Bon 
 - London :  K. Paul,  1908 
 - xv, 388 p. :  ill., plates. ;  20 cm. 
 - Half-title: International scientific series [English ed.] vol.xci .
<br/><br/> Includes index 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Force and energy<br/>Phosphorescence<br/>Radioactivity