TY - CONF AU - Weiss, Marc AU - Walls, F C2 - 8^uth^ European Frequency and Time Forum , Weihenstephan, GE DA - 1994-01-01 LA - en PB - 8^uth^ European Frequency and Time Forum , Weihenstephan, GE PY - 1994 TI - Preliminary Evaluation of Time Scales Based on Hydrogen Masers ER -