Ralph Grimaldi "Matemáticas Discreta y Combinatoria"

http://books.google.com.uy/books?id=lHqqjoR0b1YC&printsec=frontcover&dq=matematicas+discreta+y+combinatoria&source=bl&ots=gQrZgsSe_o&sig=ecV729kKNbu7jobE_NBIrkTf9uk&hl=es&ei=ttfyS7XdG4KB8gaOpujZDQ&sa=X&oi=book_result&ct=result&resnum=6&ved=0CCkQ6AEwBQ#v=onepage&q&f=false