For links to digital library software, please submit to: Reference/Libraries/Library_and_Information_Science/Software/
For links to digital libraries and online collections please submit to: Reference/Libraries/Digital/
For links to metadata, cataloguing, standards and so on please submit to their appropriate categories.
Current information on historic libraries may be better submitted in Reference: Libraries: Special Collections.
Libraries for historical research should be submitted under Reference: Libraries: Subject Specific.