This click-through agreement (the "Agreement") contains the terms and conditions applicable to use of the CrossRef system via the CrossRef API Services (including the OpenURL Service). Please read it carefully.

Terms & Conditions for Non-Commercial Use of the CrossRef API Services (the CrossRef Services)

1. Manner of Use.

 a. The User may retrieve DOI numbers and metadata via the CrossRef Services for scholarly, research, educational, personal or non-commercial purposes.

 b. The User may cache and incorporate DOIs and metadata into his or her content and systems.

 c. The User may not charge fees for access to the CrossRef Services or the DOI numbers and metadata. The User may not re-license or sell the DOI numbers and metadata or access to the service, including but not limited to bulk reproduction or distribution of the DOIs and metadata.

 d. If the User wishes to make commercial use of the DOI numbers and metadata and/or wishes to have better system response times to integrate the CrossRef Services into a commercial product or service then the User must become a CrossRef Affiliate as defined on the CrossRef website (http://www.crossref.org/).

2. Access to CrossRef Services

 a. CrossRef Services, DOI numbers and metadata are provided "as is" with no performance or quality guarantees.

 b. CrossRef reserves the right to suspend User's access to the CrossRef Services at any time in its sole discretion.