00269nam a2200109 a 450000500170000002000150001708200180003210000170005024500320006726000380009930000220013720251203090444.0  a0713515945  a515,bDD, Por  aPorter, R.L.  aFurther elementary analysis  aLoNew DelhionbBell & Hymanc1982  axi, 368p., 22 cm.