Jack, Maria. The time trippers / by Maria Jack, Ian Lister. - Singapore : McGraw-Hill, 2008. - 112 p. : ill. ; 24 cm. + 1 audio CD (4 3/4 in.) - Password readers. . - Password readers (American English). Intermediate . "Password readers - American English" -- Cover. ISBN: 9780071273725 (pbk. : Int. ed.) Subjects--Topical Terms: Readers. Dewey Class. No.: 428.6 / JAC 2008