Magayones, Judith B.  <br/><br/>
How valentine's day started :  the day was first associated with romantic love in the circle of Geoffrey Chaucer in the high middle age, when the tradition of courtly love flourished / 
Judith B. Magayones. 
 - Philippines; 	  Publishers Association of the Philippines, Inc.,   February 2018. 
 - Volume 66, pages 342-343.