The HP-21 emulation software and all associated interfaces, documentation and designs are copyright 2012 Sydneysmith.com.
This work is based on a physical calculator created by HP. All credit for the original idea, the choice of functions and the layout goes to HP.
Sydneysmith.com is not affiliated with the Hewlett Packard Company or with Hewlett Packard Australia Ltd.
Hewlett Packard and the HP logo are trademarks of the Hewlett Packard company.
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