Telemus: Meanwhile I have some doubts on the three matches quoted from Edochess. There two sources are given:
1. Di Felice, Chess Results, 1921-1930, and
2. Feenstra Kuiper, 100 Jahre Schachzweikämpfe.
Feenstra Kuiper gives Berlin as place in all cases. Jurgschat lived in Düsseldorf, Sir G.A. Thomas in England, P.S. Leonhardt probably in Hamburg and Heinz Multhaup (*1902, journalist) in Essen. So, why should these matches stage in Berlin?
I found none of the matches mentioned in DSZ 1922 or 1923 and many other sources.
Can anybody confirm one of these matches?
Does Di Felice give sources?
Regarding the match with Thomas: there was a player named Thomas on board one, when the Rheinisch-Westfälische Schachverband played against the Netherlands in 1914.