Arkowitz, Martin. <br/><br/>
Groups of homotopy classes :  rank formulas and homotopy-commutativity / 
[by] M. Arkowitz [and] C.R. Curjel. 
 - [2d rev. ed.] 
 - Berlin ;  New York :  Springer-Verlag,  1967. 
 - 35 p. ;  28 cm. 
 - Lecture notes in mathematics  4 .
<br/><br/>Bibliography: p. 34-35. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Homotopy theory.<br/>Group theory.