Variable Chaplygin Gas: Constraints from Supernovae, BAO, Look Back   Time, and GRBs
  We examine the variable Chaplygin gas (VCG) model with the aim of establishing tight constraints by using type-Ia supernovae, lookback time measurements, Baryon Acoustic Oscillations (BAO) and the Gamma Ray Bursts. We report the parameter constraints obtained via statistical analysis of cosmic observables namely, luminosity distance, BAO distance and lookback time measurement 
Bhuvan Aggarwal, Geetanjali Sethi, Shruti Thakur
astro-ph.CO