crossref.org : : free DOI guest searchCrossref currently provides a number of ways for you to locate a DOI. If you have bibliographic data for a item and would like to find the DOI, please use the metadata section of this form. If you only have an article title and author, please use the article title search section of this form. If you have the text of a bibliographic reference, please use our Simple Text Query service. If you are a
