Monoenergetic electronic beam production using dual collinear laser pulses - Thomas,AGR; Murphy,CD; Mangles,SPD; Dangor,AE; Foster,P; Gallacher,JG; Jaroszynski,DA; Kamperidis,C; Lancaster,KL; Norreys,PA; Viskup,R; Krushelnick,K; et al. (PHYSICAL REVIEW LETTERS, 2008)