Despite significant growth in the number of research papers available through open access it is estimated that only c. 20% of the number of papers published annually are open access. It is up to the authors of papers to change this. Why might open access be of benefit to authors? One universally important factor for all authors is impact. Recent studies have begun to show that open access increases impact. More studies and more substantial investigations are needed to confirm the effect, although a simple example demonstrates the effect. This chronological bibliography is intended to describe progress in reporting these studies; it also lists the Web tools available to measure impact. It is a focused bibliography, on the relationship between impact and access.