Guest Post: Charles Oppenheim Asks How Big a Problem Are Articles that Should Be OA but End Up Behind Paywalls - The Scholarly Kitchen

"Over the past several years, some online commenters have uncovered examples of publishers failing to make freely available articles for which an article processing charge had been paid for that very purpose. After raising this issue recently in response to a Scholarly Kitchen posting, one of our regular commenters investigated the issue more closely. This is his report."