Penner, R. C. <br/><br/>
Combinatorics of train tracks / 
R.C. Penner with J.L. Harer 
 - Princeton  Princeton University Press  1992 
 - xi, 216 p.   ill. ;  24 cm. 
 - Annals of mathematics studies   no. 125 .
<br/><br/> TB1420<br/>$ 99.95 
<br/><br/><label>ISBN: </label>9780691025315 (pbk.) 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Geodesics (Mathematics)<br/>CW complexes.<br/>Combinatorial analysis.
<br/><br/><label>Dewey Class. No.: </label>511.6 PEN