HP-28 series - Wikipedia

HP Inc. - Wikipedia

HP LaserJet - Wikipedia

Final Fae merge, +spd/-hp or +def/-hp?

HP Vectra VL400 MT - Higher Intellect Vintage Wiki

Pratt & Whitney R-4360 Wasp Major - Wikipedia

Fiat 28-40 HP - Wikipedia

File:HP-28S (2).jpg - Wikimedia Commons

Hewlett-Packard - Wikipedia

FOUR ELECTRIQUE LUXELL LX9645 70 L NOIR

National Museum of American History

The HP wiki really has a page for every day of the year

HP calculators - Wikipedia