books.google.com - This text is designed to teach the ten-key tough method of operating print, display-print, or display calculators. It also teaches simple math operations using the calculator....https://books.google.com/books/about/Calculators.html?id=8AILAAAACAAJ&utm_source=gb-gplus-shareCalculators
William R. Pasewark, Sr., earned the PhD at New York University. He taught both Business and Education courses at NYU, Michigan State, Penn State, and Texas Tech. Pasewark authored 105 best-selling business and computer books, seven of which won Texty Awards from the Text and Academic Authors Association. Work experience includes several jobs in the Wall Street section of NYC; Office Management Consultant; Marine Corps Sergeant in the Iwo Jima Invasion; General Manager of Pasewark LTD, a textbook authoring family partnership. Pasewark lectured in 31 states and several foreign counties. He attended 60 continuous NBEA conventions and was a registered lobbyist to require business courses in high schools.