Or...look at these! Dajjal, thanks for the tip on the “Shorter Summa” - I am going to get it.
http://www.catholiccompany.com/display_results.cfm?search_string=summath&aid=283&new=yes&OVRAW=summa&OVKEY=summa&OVMTC=standard&OVADID=19404543522&OVKWID=110094096522
(Hope this link posts OK)