863-865 Subfield $w - Break indicator:

Subfield $w contains a one-character code that indicates the reason for a break in the enumeration and chronology.

A break in the enumeration and chronology contained in multiple 863-865 fields is due either to published issue(s) lacking in the collection or to unpublished parts or a lack of continuity in the enumeration and chronology of the parts.  Subfield $w is contained in the Enumeration and Chronology field that represents the holdings that immediately precedes the break.  The use of subfield $w requires a new field 863-865 in which the enumeration and chronology following the break is recorded.

g - Gap break:  Code g indicates that part(s) are lacking in the holdings of the reporting organization.  Code g is also used when there is doubt as to the cause of the break or when the cause is not known.

Example:

853  03  $81$aBd.$i(year)

863  40  $81.1$a1-19$i1911-1920/1921$wg

863  41  $81.2$a22$i1924/1925

[A gap occurs in the holdings between v.19 and v.22.]

n - Nongap break:  Code n indicates that the break is due to unpublished part(s) or a lack of continuity in the enumeration and chronology of the parts.

Examples:

853  20  $81$a(year)

863  40  $81.1$a1900-1915$wn

863  40  $81.2$a1917-1940

[The holdings record contains no Enumeration and Chronology field for the nonpublished pieces.  The nongap break is indicated by the code in subfield $w in the 863 field immediately preceding the break.]

853  20  $81$av.$i(year)

863  40  $81.1$a1-3$i1958-1960$wg

863  40  $81.2$a5-7$i1962-1965$wn

863  44  $81.3$a9-10$i1967-1968$wg

863  40  $81.4$a13-14$i1971-1972

[The reporting organization lacks volumes 4, 8, and 11-12.  The second and third Enumeration and Chronology fields reflect both a nongap (v. 9-10) and a gap break (v. 11-12).]

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