----------------------------Original message---------------------------- I cannot answer this question as I do not use OCLC. However we have fixed this dilemma in the CCK (former Dutch Union Map Catalogue) by using UNIMARC tags 100 and 122. However these are used for indexing and information-retrieval. In tag 100 it is possible to state "type of publication date": a= currently published serial b= serial no longer being published c= serial of unknown status d= monograph complete when issued, or issued within one calendar year e= reproduction of a document f= monograph, date of publication uncertain g= monograph whose publication continues for more than a year h= monograph with both actual and copyright/privilege date i= monograph with both release/issue date and production date j= monograph with detailed date of publication e.g.: Topographic map of the Netherlands 1945-... = A19459999 facsimile of Le Grand atlas published 1967= E16631967 In tag 122 it is possible to state "time period of item contents" We created 5 possibilities: 1= time period is one date 2= time period is two dates 3= time period is three dates 4= time period is between two dates 5= time period is estimated between two dates e.g.: Remote sensing image 2 august 1976, 14:08 h: 1 +1976080214 facsimile of Le Grand Atlas published 1967: 5 +1646 +1663 Of course this coded information is accompanied by verbal statements in the publication-field and note-field to allow output of ISBD-descriptions. Jan Smits Mapcurator Royal Library, National Library of The Netherlands [log in to unmask]