See section 5.2.1 in https://www.google.ch/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwjk0a3hzNnLAhUFxRQKHRvvCgsQFggcMAA&url=https%3A%2F%2Fepb.bibl.th-koeln.de%2Ffiles%2F282%2FCarevic.pdf&usg=AFQjCNG_sDCGruV1hijuHfw4YrEhYn-00Q
