After that brief detour for Going Mobile : Responsive Ads, let's return to Korchnoi's Events 1977-1996. The original PGN file I used for that 1977-1996 post appears to have been from the 1990s UPITT collection and was named KORCH2PG.ZIP. It contained a file called FILE_ID.DIZ (what did a DIZ extension mean?) which informed:-
Expanded Viktor Korchnoi Collection:
3995 Games, from W. G. Sanderse.
After I worked on that file, I found a second ZIP file in my own archive, originally from GM Khalifman's GMchess.com site. It was a good chess site for its time, but seems to have disappeared in 2007; it lives on at Archive.org: /web/*/gmchess.com. The original file contained 3832 Korchnoi games, of which 2282 were from the years 1976 to 2001. I added a summary of the file's contents for that period to my page on Viktor Korchnoi's Tournament, Match, and Exhibition Record (1946-1977), aka 'Korchnoi's TMER'.
Although the GMchess file is better organized than the UPITT file, it's not perfect. The following table shows the summary of Brussels events from the 1980s.
As I recounted in My Two Encounters with Korchnoi (June 2016), I witnessed many of these events and am certain that the three events for 1986 were in fact two events; ditto for 1987. That leaves me with some work to merge and correct the two sources -- UPITT 1977-1996 & GMchess 1976-2000 -- plus add events Korchnoi played after 2000.