inventions get the inside story on gadgets and systems past and present / [[Book] :] TheBritannica learning library. - india : BPI india pvt LTD, 2009. - 64 p : ill ; 30 cm. - Britannica family . Young Readers. ISBN: 9788184970678 Subjects--Topical Terms: inventions--encyclopaedia. Dewey Class. No.: 031 National Library of Medicine Call No.: / BI