Today I had a need to think about how to do a reverse lookup of a formatted citation to find a DOI. @CrossrefOrg helped out and pointed me to the reverse api endpoint. It workes like this: http://api.crossref.org/reverse Created a json payload file “citation.json” formatted as follows: [ " Curtis, J. R., Wenrich, M. D., Carline, J. D., Shannon, S. E., Ambrozy, D. M., & Ramsey, P. G. (2001). Understanding physicians’ skills at providing end-of-life care: Perspectives of patients, families, and health care workers. ... (more)