A co-author paper was published in Atmosphere journal as an outcome of CEReS International Joint Research Program. Kang M., K. Ichii, J. Kim, Y.M. Indrawati, J. Park, M. Moon, J.H. Lim, J.H. Chun (2019) New gap-filling strategies for long-period flux data gaps using data-driven approach. Atmosphere, 10, 568.