##' visualizing phylogenetic tree and heterogenous associated data based on grammar of graphics
##' \code{ggtree} provides functions for visualizing phylogenetic tree and its associated data in R.
##'
##' If you use ggtree in published research, please cite:
##' Guangchuang Yu, David Smith, Huachen Zhu, Yi Guan, Tommy Tsan-Yuk Lam.
##' ggtree: an R package for visualization and annotation of phylogenetic trees with their covariates and other associated data.
##' Methods in Ecology and Evolution 2017, 8(1):28-36, doi:10.1111/2041-210X.12628
##'
##' @docType package
##' @name ggtree
##' @aliases ggtree package-ggtree
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