National Union Catalog

AAP AB 1905+ ABSR etc., is the library holdings information. Libraries are identified by their National Union Catalog symbols, and holdings are shown by inclusive years. 

I. National Union Catalog Fre-i 6 Imprints, 754 vols. (London Mansell, 1968-1981), nos. P0436278-P04362.80. 

The REMCO publishes a directory for RMs and has gathered information on more than 1500 CRMs that were available or under preparation in 2002. In addition, the International Union of Pure and Applied Chemistry (lUPAC) issues a catalog of available CRMs. Some additional compilations of existing CRMs exist in more specialized fields, e.g., marine monitoring (publications of the National Oceanographic and Atmospheric Administration, USA). 

---