Haurongo: O'Regan, Patrick Joseph
He whakaaturanga anō
Rārangi pukapuka
'Hon. Mr Justice O'Regan: his interesting career'. New Zealand Law Journal. 1 June 1937: 141--143, 147
O'Regan family. Diaries and papers, 1893--1988. MS Group 273. WTU
Sweetman, R. M. 'Patrick Joseph O'Regan, 1869--1947: a life of advocacy'. Turnbull Library Record 21, No 2 (Oct. 1988): 93--97