TY - JOUR AU - Peter Bender BT - Physical Review DA - Jan-06-1964 DO - 10.1103/PhysRev.134.A1174 PY - 1964 SP - A1174 EP - A1180 T2 - Physical Review TI - Interpretation of Frequency Shifts Due to Electron Exchange Collisions VL - 134 SN - 0031-899X ER -