The pebbling number of C5 × C5. - David S. Herscovici; Aparna W. Higgins (Discret. Math., 1998)

Maximum Degree Growth of the Iterated Line Graph. - Stephen G. Hartke; Aparna W. Higgins (Electron. J. Comb., 1999)

Minimum Degree Growth of the Iterated Line Graph. - Stephen G. Hartke; Aparna W. Higgins (Ars Comb., 2003)