Halmos Paul Richard: Limits of shifts. In: Acta scientiarum mathematicarum, (34). pp. 131-139. (1973)
Halmos Paul Richard: Quasitriangular operators. In: Acta scientiarum mathematicarum, (29) 3-4. pp. 283-293. (1968)
Brown Arlen and Halmos Paul Richard and Shields Allen Lowell: Cesàro operators. In: Acta scientiarum mathematicarum, (26) 1-2. pp. 125-137. (1965)
Halmos Paul Richard: Numerical ranges and normal dilations. In: Acta scientiarum mathematicarum, (25) 1-2. pp. 1-5. (1964)
Halmos Paul Richard: Commutativity and spectral properties of normal operators. In: Acta scientiarum mathematicarum, (12). pp. 153-156. (1950)