What is the fine-grained topic of the following text: This collection of essays, representing recent research in the archives at the British library, examines the firms' astute business strategy during the nineteenth century, its successful expansion into overseas markets in America and India, its complex and intriguing relations with authors such as Matthew Arnold, Thomas Hardy, Alfred Lord Tennyson, W.B.Yeats, and J.M.Keynes, with additional chapters on Macmillan Magazine and the work of a modern children's editor. Only return the topic.
Research on Macmillan Publishing's business strategy and author relationships in the 19th century.