DM41L : Office Products
HP 46 Desktop Calculator from 1973
software for HP42s - TheCalculatorStore
HP 42S Scientific Calculator from 1988
HP Forums - How to open a 49G?
HP-42S - Wikipedia
HP calculators - Wikipedia
L'arte dimenticata dei calcolatori programmabili HP in Reverse Polish Notation (RPN) – Gioorgi
Emulators
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