Limit Fields

The limit fields listed below are specially indexed fields that have relatively few possible values. They allow you to limit your searches to records of a particular characteristic, such as type of publication or language of article.

Accession Number (AN)

CODEN (CO)

Country of Publication (CP)

Document Type (DT)

EMCLAS Classification (EC)

ISBN/ISSN (International Standard Numbers) (IS)

Journal Name (JN)

Language of Article (LA)

Language(s) of Summary (LS)

Publication Type (PT)

Publication Year (PY)

Update (UD)

Record Features (XREC)

You can search these fields with in or =. For example, to retrieve documents originally published in French, type:

french in la or la=french

In addition to in and =, in some fields that contain only numbers, you can use one of the following special operators:

This field contains the year in which the document was published. You can search the PY field with the following operators, as well as with in and =:

< less than,

such as py<1990

> greater than,

such as py>1991

<= less than or equal to,

such as py<=1989

>= greater than or equal to,

such as py>=1992

- within a range,

such as py=1990-1992