Alexander Bolotov Artie Basukoski A clausal resolution method for branching-time logic ECTL<sup>+</sup>. 235-263 2006 46 Ann. Math. Artif. Intell. 3 http://dx.doi.org/10.1007/s10472-006-9018-1 db/journals/amai/amai46.html#BolotovB06