The 2003 IEEE TSE paper “Model-Checking Algorithms for Continuous-Time Markov Chains” by Christel Baier, Boudewijn Haverkort, Holger Hermanns, and Joost-Pieter Katoen is ranked 74 in the top-100 of most cited papers in software engineering (and ranked 57 in the top-100 when considering number of citations per year).  The top-100 has recently been published in Information & Software Technology (see paper) and is based on surveying 70,000 papers.