Klippenstein, Stephen; Sivaramakrishnan, Raghu; Burke, Ultan; Somers, Kieran; Curran, Henry; Cai, Liming; Pitsch, Heinz; Pelucchi, Matteo; Faravelli, Tiziano; Glarborg, PeterH2 + H2: High Level Theory and the Role of Singlet Channels Combustion and Flame(2022)