October 13 (SeeNews) - The main equity indices of the Zagreb Stock Exchange (ZSE) slightly advanced on Wednesday as gains in the share price of hotel operator Valamar Riviera [ZSE:RIVP], ICT solutions provider Ericsson Nikola Tesla [ZSE:ERNT], and food and pharmaceuticals producer Podravka offset losses in telco Hrvatski Telekom [ZSE:TH], bourse data showed.