diff --git a/DESCRIPTION b/DESCRIPTION
index bbb49e5..72ce24c 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -3,10 +3,10 @@ Title: PhyloseqExtended
 Version: 0.1.0.9000
 Authors@R: 
     person(given = "Mahendra",
-           family = "Mahendra",
+           family = "Mariadassou",
            role = c("aut", "cre"),
            email = "mahendra.mariadassou@inra.fr")
-Description: Adds severals additional functions to phyloseq, mainly used for training.
+Description: Adds severals additional functions to phyloseq (rarefaction curves, phylogenetic diversities, specificity and prevalence indices, nice composition plots, etc). Mostly used during training sessions. 
 License: GPL-3
 Encoding: UTF-8
 LazyData: true
diff --git a/NAMESPACE b/NAMESPACE
index 22a6078..f7aa0b6 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -2,6 +2,7 @@
 
 export(estimate_local_specificity)
 export(estimate_prevalence)
+export(fast_tax_glom)
 export(ggformat)
 export(ggpdrare)
 export(ggrare)
@@ -24,5 +25,6 @@ importFrom(biomformat,biom_data)
 importFrom(biomformat,read_biom)
 importFrom(biomformat,sample_metadata)
 importFrom(plyr,rbind.fill.matrix)
+importFrom(tibble,column_to_rownames)
 importFrom(vegan,ordilabel)
 importFrom(vegan,specnumber)
diff --git a/R/richness.R b/R/richness.R
index e17816f..2918d49 100644
--- a/R/richness.R
+++ b/R/richness.R
@@ -1,6 +1,3 @@
-require(parallel)
-options(mc.cores= 2)
-
 #' Phylogenetic diversity
 #'
 #' @param physeq phyloseq class object, from which phylogeny and abundance data are extracted
@@ -46,7 +43,6 @@ phylodiv <- function(physeq, theta = 0) {
     return(pd)
 }
 
-
 #' Rarefaction curves for phylogenetic diversity, ggplot-style
 #'
 #' @inheritParams ggrare
diff --git a/R/specificity_methods.R b/R/specificity_methods.R
index 20c3719..4d4dff5 100644
--- a/R/specificity_methods.R
+++ b/R/specificity_methods.R
@@ -3,6 +3,7 @@
 ## Compute specificity of a vector
 ## x represents (possibly not normalised) distribution of quantity
 ## of interest across conditions
+#' @keywords internal
 specificity <- function(x, index = c("shannon", "simpson", "yanai", "indspec"), groupfrac = NULL) {
     ## Args:
     ## - x: matrix (vectors are automatically coerced to 1-row matrices), specificity
@@ -54,6 +55,7 @@ specificity <- function(x, index = c("shannon", "simpson", "yanai", "indspec"),
 ## Compute local specificity of a vector
 ## x represents (possibly not normalised) distribution of quantity
 ## of interest across conditions
+#' @keywords internal
 local_specificity <- function(x, index = c("fraction", "indspec"), groupfrac = NULL) {
     ## Args:
     ## - x: matrix (vectors are automatically coerced to 1-row matrices), specificity
diff --git a/man/top_taxa.Rd b/man/top_taxa.Rd
index 40998d7..7a785e5 100644
--- a/man/top_taxa.Rd
+++ b/man/top_taxa.Rd
@@ -14,7 +14,7 @@ top_taxa(physeq, taxaRank = NULL, numberOfTaxa = 9)
 \item{numberOfTaxa}{Number of top taxa to return}
 }
 \value{
-A character vector the the `numberOfTaxa` most abundant `taxaRank`-level taxa
+A matrix corresponding to the `numberOfTaxa` most abundant taxa at level `taxaRank`-level
 }
 \description{
 Find the most abundant taxa at a given taxonomic rank