Rossi X‐Ray Timing Explorer Absolute Timing Results for the Pulsars B1821−24 and B1509−58
                         
                    
                    
                    
                        - Authors: A.
H. Rots, K. Jahoda, D.
J. Macomb, N. Kawai, Y. Saito, V.
M. Kaspi, A.
G. Lyne, R.
N. Manchester, D. C. Backer, A.
L. Somer, D. Marsden, and R.
E. Rothschild
                        Rots  et al. 
                        1998 The Astrophysical Journal 501
                         749.