Paper I: Phase Transition in a System of Random Sparse Boolean Equations, Thorsten E. Schilling, Pavol Zajac, Tatra Mountains Mathematical Publications 45, 1–13, (2010). The paper is available in BORA: http://hdl.handle.net/1956/6193Paper II: Solving Equation Systems by Agreeing and Learning, Thorsten E. Schilling, Håvard Raddum, Springer Lecture Notes in Computer Science 6087, 151–165, (2010). The paper is available in BORA: http://hdl.handle.net/1956/6194Paper III: Analysis of Trivium Using Compressed Right Hand Side Equations, Thorsten E. Schilling, Håvard Raddum, Springer Lecture Notes in Computer Science 7259, 18–32, (2012). The paper is available in BORA: http://hdl.handle.net/1956/6192Paper IV: Solving Compressed Right Hand Side Equation Systems with Linear Absorption, Thorsten E. Schilling, Håvard Raddum, Sequences and their Applications, Waterloo, to appear in Springer LNCS, (2012). The paper is available in BORA: http://hdl.handle.net/1956/6195