On Period and Burst Histories of AXPs and SGRs and the Possible   Evolution of these Objects on the P-Pdot Diagram
  In this paper, timing data for all of the anomalous X-ray pulsars and soft gamma repeaters are compiled. Timing properties of these objects are investigated. The effect of bursts of soft gamma repeaters on their period history is investigated. The P-Pdot diagram for pulsars, X-ray binaries, anomalous X-ray pulsars, soft gamma repeaters and dim radio quiet netron stars is constructed. The possible evolutionary tracks for anomalous X-ray pulsars, soft gamma repeaters and dim radio quiet netron stars are examined. 
Oktay H. Guseinov, Efe Yazgan, Askin Ankay, and Sevinc Tagieva