Eduardo, Ericson J. Crossing the boundaries of time/ Ericson J. Eduardo and Sarah Jane R. Vergara. - Philippines: In the Grade School, Inc., c2011. - v60 n4, pages 140-144: illustrations; 227cm. ISSN: 2094-8042 Subjects--Topical Terms: Education. Dewey Class. No.: DPer 370.105 M72 Jan-Dec 2011 v59-60