scientific article published in 1963

scientific article published in 1964

scientific article published in December 1963

doctoral dissertation by Alfréd Rényi

scientific article published in 1970

scientific article published in 1959

scholarly article from 'Publicationes Mathematicae Debrecen' published in 1959

scholarly article from 'Acta Mathematica Academiae Scientiarum Hungaricae' published in 1963

scientific article published in September 1966

scientific article published in 1951

scientific article published in March 1956

scientific article published in March 1964

article published in 1953

scientific article published in May 1963