August 5 (SeeNews) - Croatian hotel operator Valamar Riviera [ZSE:RIVP-R-A] swung to a negative consolidated EBITDA of 107.9 million kuna ($17.1 million/14.4 million euro) in the first half до 2020, from a positive 84.7 million kuna EBITDA in the like period of 2019, it said.