# - Undefined
# - Undefined
|$a - Topical term or geographic name entry
$b - Topical term following geographic name entry element (NR)
$i - Relationship information (R)
$v - Form subdivision (R)
$w - Control subfield (NR)
/0 - Special relationship
/1 - Tracing use restriction
/2 - Earlier form of heading
/3 - Reference display
|$x - General subdivision (R)
$y - Chronological subdivision (R)
$z - Geographic subdivision (R)
$0 - Record control number (R)
$4 - Relationship code (R)
$5 - Institution to which field applies (R)
$6 - Linkage (NR)
$8 - Field link and sequence number (R)
Tracing for a topical term see also from reference.
Used in an established heading or established heading and subdivision record to trace a see also from reference from an established topical term to a related established heading.
Most of the content designators defined for field 550 are the same as those defined for field 150 (Heading-Topical Term), field 450 (See From Tracing-Topical Term), and field 750 (Established Heading Linking Entry-Topical Term). Description, guidelines, and input conventions for shared content designators are given in the X50 Topical Terms-General Information section.
Guidelines for using subfield $w (Control subfield), subfield $i (Relationship information), and subfield $4 (Relationship code) in field 550 are given in the Tracings and References-General Information section.
|150||##$aSand Creek Massacre, Colo., 1864|
|550||##$wg$aIndians of North America$xWars$y1862-1865|