The escalating price of scholarly journals has been a cause of concern for researchers, research institutions, and libraries. The library literature is replete with studies of pricing trends and assessments of impact; a small selection of resources is offered here.
Price per article and price per citation data, Ted Bergstrom and Preston McAfee
"Periodical Price Survey 2008: Embracing Openness," Lee C. Van Orsdel and Kathleen Born, Library Journal, April 2008
"19th Annual Study of Journal Prices for Scientific and Medical Society Journals," [PDF] Gene Kean, JP: Newsletter for Journal Publishers, 2007
"Scholarly Journal Prices: 2000-2006," Sonya White and Claire Creaser, 2007