A stochastic model for the publishing and citation process is discussed in Detecting h-index manipulation through self-citation analysis, from the fraud-detection point of view of the OP. The functional form of the h-index curve following from this model is a sum of incomplete Beta functions, with parameters the productivity of the researcher and the career length.
One telltale signal is the "humpback", resulting from self-citation of a paper close the the h-index.
