Times of Minimum Database
BAV
BRNO
AAVSO
ROCZNIK ASTRONOMICZNY / Krakow
AN ATLAS OF O-C DIAGRAMS OF ECLIPSING BINARY STARS / Krakow
TIDAK
Bob Nelson's O-C files
Catalog
General Catalog of Variable Stars
The 9th Catalogue of Spectroscopic Binary Orbits
Search NStED for an Individual Star
VizieR
Photometry Datas
VSOLJ Light Curve Generator
KWS
ASAS-3
HIPPARCOS
Checker
Comet Checker
Minor Planet Checker