Abstract
All nurse researchers need to address, in the manner most appropriate to their research methodology, issues of quality related to their research material. This concern is not about the care needed in generating data, rather it relates to understanding and evaluating material that already exists. This article describes four historical sources relevant to the history of nursing in New Zealand and uses them to explain how nurse researchers can evaluate their research material. The dimensions of this evaluation are the provenance, purpose, context, veracity and usefulness of the historical sources. The article explains the questions that need to be addressed in each dimension of the evaluation. The different kinds of information available in the four historical sources are illustrated by references to individual nurses.

Keywords
History of nursing, historical research, research methodology, nurse researchers