Cartmell, E. <br/><br/>
Valency and molecular structure / 
E. Cartmell & G.W.A. Fowles. 
 - ELBS ed. of 4th ed. 
 - London :  English Language Book Society and Butterworths,  1977. 
 - 341 p. 
<br/><br/><br/>1979 reprint. 
<br/><br/><label>ISBN: </label>0408709227 
<br/><br/><label>LCCN: </label>91036054     
<br/><br/><label>Subjects--Topical Terms: </label><br/>Valence (Theoretical chemistry)<br/>Molecular structure.