Some Invariant String Cosmological Models in Cylindrically Symmetric   Space-time
  In this paper we derive some new invariant solutions of Einstein-Maxwell's field equations for string fluid as source of matter in cylindrically symmetric space-time with Variable Magnetic Permeability. We also discuss the physical and eometrical properties of the models derived in the paper. The solutions, at least one of them, are interesting physically as they can explain the accelerating as well as singularity free Universe. 
Ahmad T. Ali, Anil Kumar Yadav, Farook Rahaman and Arkopriya Mallick
gr-qc