When assigning GAC's for time periods that straddle the 1991 period, many times the GAC must be doubled.

Example
043 -- e-ur---‡ae-ru---
100 1- Rubenstein, Joshua.
245 10 Tangled loyalties :‡bthe life and times of Ilya Ehrenburg /‡cJoshua Rubenstein.
...
600 10 Erenburg, Ilia,‡d1891-1967.
650 -0 Authors, Russian‡y20th century‡xBiography.
650 -0 Journalists‡zSoviet Union‡xBiography.
650 -0 Communism and culture‡zSoviet Union.
651 -0 Soviet Union‡xIntellectual life‡y1917-1970.
DCLC9536588-B