Keene Carolyn. The clue of the tapping heels/ Keene C. - New York : Grosset & Dunlap. 1997 - 214 pages. - Nancy drew mystery stories.. . Trouble The Guardian The Flight... English hbk. ISBN: 9780448095165 Subjects--Topical Terms: Tap code FictionChildren stories Dewey Class. No.: 823 KEE-C 3832