Literary notes and drafts of Anne McCosker's poems and stories, personal correspondence, research papers and correspondence relating to the history of Australian New Guinea before and after World War Two, World War One letters from Lieutenant F.W.S. (Fred) Martin, and photographs relating to Anne McCosker's family history in Australian New Guinea. Many of the letters, research documents and photographs relating to New Guinea were used as source material for Anne McCosker's book Masked Eden: A History of the Australians in New Guinea.

Handwritten and typed drafts of Anne McCosker's poems and short stories, often with heavy editing and annotations, and notes and drafts for the book Lieutenant Martin's Letters. Many of the drafts of poems and stories are in notebooks. The series also contains a typed draft of a story titled 'Pacific Pot Pourri: Concerning One Klearwatgear', written during World War 2 by Winifred Martin.

Letters and cards received or written by Anne McCosker and letters collected by her and used as source material for her books about Lieutenant Frederick Martin and the history of Australians in the colonial territory of New Guinea.