fx-991ES and fx-115ES Practice Calculations: Using the Casio fx-991ES Plus and fx-115ES Plus Calculators: Brown, Allen: 9781693746963: Amazon.com: Books
Amazon.com : FitSand Hard Case Compatible for Casio FX-991ES Plus Scientific Calculator : Office Products
Amazon.com : NEWYES 991ES Scientific Calculators with Writing Tablet, Advanced 417 Function Solar Energy LCD Notepad Science Calculators, Professional Foldable Calculators for Students School and College : Office Products