Roelf Backus:
hp67_hp35s
Roelf Backus:
Hewlett Packard hp67
Roelf Backus:
Hewlett Packard hp67_Canon AE1_B&L BalGrip eyewear
Roelf Backus:
Hewlett-Packard hp67_Canon AE1_Ray Ban BalGrip
Roelf Backus:
hp-35s
Roelf Backus:
hp-35s (2)
Roelf Backus:
Hewlett Packard hp67 programmable calculator
Roelf Backus:
hp67 & hp35s
Roelf Backus:
HP-67 calculator display LED
Roelf Backus:
HP-67 programmable scientific calculator with magnetic memory cards (1976)
Roelf Backus:
hp67_keyboard_keys_softfocus