Trigonometry worktext / 
Rodolfo G. Tungcab [and five others]. 
 - Manila :  Grandbooks Publishing, Inc,  2013. 
 - v, 105 pages :  illustrations ;  26 cm. 
<br/><br/> References: p.103. 
<br/><br/><label>ISBN: </label>9789717251516 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Trigonometry.