diagonal: <Lucerne 1949>, International Invitation Tournament, pretty strong field back then:
1. Max Blau 5/7
(His biggest tournament cap)
Braslav Rabar 4.5
(Yugoslavia hosted the first Olympiad after World War II in Dubrovnik in 1950. The host team finished first, and Rabar, with the score of eight wins and two draws (90%), won an individual board Gold medal)
Wolfgang Unzicker 4.5
(Rapidly rising German, an elite player for decades, Lucerne tournament title defender from 1948, and again winner at Lucerne in 1951)
Henry Grob 4.5
(Winner at Ostende 1937 as best on tie-break, together with Fine and Keres; first Swiss player to be awarded as an IM in 1950 at its FIDE title inauguration; today remembered for popularizing "Grob's Attack" 1.g4, ... well, 1.g3 seems perfectly sound)
5. Hans Müller
(Austrian Author and multiple player at the Olympiads between 1928 and 1950)
(Back then a strong Dutchman, regular player for The Netherlands at the Olympiads between 1950 and 1962; today best known perhaps for co-authoring 'The Middle Game' with Max Euwe)
(Apparently the last major tournament of legendary Znosko-Borovsky, then playing for France)
8. Serge Tordion
(Swiss Champion that year 1949, surprising winner in 1947, the first edition of the Lucerne series wasn't as strong as the follows-up)
The International Lucerne series lasted annually from 1947 to 1953, most prominent winner was Max Euwe in 1950 (joint with Pilnik).
Further prominent players at Lucerne, amongst others: Kottnauer (who won in 1952), Sämisch, Paoli, Barden, Prameshuber, Chantal Chaudé de Silans, and from Switzerland Martin Christoffel, Josef Kupper, Edwin Bhend or Peter Leepin (winner in 1953).
Unfortunately, no games from the winner, Max Blau.
A notable game from that event: B Rabar vs Znosko-Borovsky, 1949