dztpln                  The zero-truncated compund poisson-lognormal
                        distributions
dztplnm                 The zero-truncated compund poisson-lognormal
                        distributions mixture
ztplnMLE                MLE for the Zero-truncated Poisson Lognormal
                        distribution
ztplnmMLE               MLE for the Zero-truncated Poisson Lognormal
                        mixture distribtuion
