Roboto:100,100i,300,300i,400,400i,500,500i,700,700i,900,900i:cyrillic,cyrillic-ext,greek,greek-ext,latin-ext,vietnamese
Roboto+Slab:100,300,400,700:greek-ext,cyrillic,latin-ext,cyrillic-ext,vietnamese,latin,greek
Open+Sans:300,300i,400,400i,600,600i,700,700i,800,800i:cyrillic,cyrillic-ext,greek,greek-ext,latin-ext,vietnamese