On Reserve at the Library:
Kleerekoper H, Timms AM, Westlake GF, Davy FB, Malar T, Anderson VM. 1970. An analysis of locomotor behaviour of goldfish (Carassius auratus). Animal Behaviour 18(2): 317–330.
"The movements of individually observed naive goldfish, 25 to 30 cm long, in a novel ‘open field’ [...]."