whiteshark: "He won a match against Johannes Pedersen (1.5Ė0.5) at Aalborg 1927,
tied for 2nd-3rd in Danish Championship at Vordingborg 1927 (Erik Andersen won),
shared 2nd at Copenhagen 1927 (Politiken, Gťza Marůczy won),
tied for 5-6th at Copenhagen 1928 (Aron Nimzowitsch won),
tied for 7-9th at Svendborg 1930 (DEN-ch, Andersen won),
and won a simultan game against Alexander Alekhine at Copenhagen 1930.
Ruben played four times for Denmark in Chess Olympiads in 1927, 1928, 1930, 1931, and won team silver medal at London 1927."
= = =
He also won the City championship of Copenhagen <KÝbenhavnsmestrene> in 1929
He also wrote a book <Skak>