- O descobrimento da Australia pelos portuguezes em 1601
- Oamaru and the Waitaki
- Obrazki z krakowskiej nędzy.
- Observations of a Naturalist in the Pacific Between 1896 and 1899: Vanua Levu, Fiji, and Plant-Dispe...
- Oceanian Journeys and Sojourns
- Ochre and Rust
- Octopus Crowd
- Oh! What An Outback Show!
- Okitiki Terra Incognita Hokitika / Westland
- Old Bucky & Me
- Old England and New Zealand: the Government, Laws, Churches, public institutions, and the resources ...
- Old Melbourne Memories
- Old New Zealand: A Tale of the Good Old Times And a History of the War in the North against the Chie...
- Old New Zealand: Being Incidents of Native Customs and Character in the Old Times
- Old New Zealand: being incidents of native customs and character in the old times. By a Pakeha Maori...
- Old-Timers
- On Ops
- On Ops
- On Our Doorstep
- On Patriotism
- On The Block: Rocks, Rabbits and Reptiles
- On the Home Front
- On the Maori Races of New Zealand. (New Zealand Exhibition, 1865. Ethnology.).
- On the Wallaby: or, Through the East and across Australia. Illustrated, etc.
- On Track
- One Blood
- Operation Backhander
- Operation Galvanic
- Operazione Torre di Guardia
- Opposition Vanishing
- Ordinary Men, Extraordinary Service
- Origins of the Maori Wars
- Orphans of the Living
- Our Antipodes: or, Residence and Rambles in the Australasian Colonies, with a glimpse of the Gold-Fi...
- Our Antipodes: or, Residence and Rambles in the Australasian Colonies, with a glimpse of the Gold-Fi...
- Our Anzac Story
- Our Australian Cousins.
- Our Great Hearted Men
- Our Little Town
- Our New Colony, Fiji, its history, progress and resources. Edited by H. S. Cooper
- Out of Luck
- Out of the Silence
- Outback Odyssey: Travels in Hidden Australia
- Outcasts of the Gods?
- Outpost A Doctor on the Divide
- Over the Hills and Far Away: a story of New Zealand.
- Over the Mountains of the Sea
- Over the Top
- Over the Top' with the Third Australian Division (WWI Centenary Series)