Improving discoverability, if not access

Jeffrey Pomerantz, Google Scholar and 100% Availability of Information, Information Technology and Libraries, 25, 1 (2006) pp. 52-56. 

Abstract:   This paper discusses Google Scholar as an extension of Kilgour's goal to improve the availability of information. Kilgour was instrumental in the early development of the online library catalog, and he proposed passage retrieval to aid in information seeking. Google Scholar is a direct descendent of these technologies foreseen by Kilgour. Google Scholar holds promise as a means for libraries to expand their reach to new user communities, and to enable libraries to provide quality resources to users during their online search process.

From the body of the paper:

Google Scholar does not provide access to 100% of information resources in existence; but rather enables discovery of information resources, and allows for the possibility that these resources will be discoverable by the user 100% of the time.