Akiba Kiwelowicz Rubinstein ( 12 December 1882 - 15 March 1961 ) was a Polish chess Grandmaster at the beginning of the 20th century .
Akiba Rubinstein ( Stawiski , Poland , 12 December 1882 - 15 March 1961 , Antwerp , Belgium ) was a Polish chess Grandmaster in the first part of the 20th century .