TY - JOUR AU - Ye, Jun AU - Ma, L AU - Hall, John C2 - Optics Letters DA - 1996-01-01 LA - en M1 - 21 PB - Optics Letters PY - 1996 TI - Sub-Doppler optical frequency reference at 1.064 micrometers via ultrasensitive cavity-enhanced frequency modulation spectroscopy of C2HD overtone transition ER -