Proposes a mathematical model using the probability formalism to explain why a geometrical law is observed in distributions related to library circulation data. Highlights include techniques based on convolution theory; Lotka's law; and Bradford's law. (Author/LRW)

Describes two mathematical models of the periodical publishing process based on a theoretical analysis. Discusses the publishing process for periodical literature, explains the continuous model and the discrete model, presents partial differential equations, and demonstrates the adaptability and the validity of the models. (LRW)