The Twin Guide By Books / Paperback Science, Technology, Engineering, Mathematics › Computers Publisher: Mosaic Software, January 1984 Price $29.29 Free Shipping Send to a friend Used - Good Good condition. Disk not included. (computer, software, guide) A copy that has been read but remains intact. May contain markings such as bookplates, stamps, limited notes and highlighting, or a few light stains. $29.29 1 in Stock at Warehouse Quantity Add Free Shipping to continental U.S. OR $1.00 per item discount if shipped to store.