diff --git a/.Rbuildignore b/.Rbuildignore
index 1190ce12dd39d68115ef49ea42cc7c2046328ce1..ec2fc7f29ce71c3f0c6b5784d6a84a13e21bb913 100644
--- a/.Rbuildignore
+++ b/.Rbuildignore
@@ -2,6 +2,7 @@ README.md
 Rplots.pdf
 contributing.md
 buildPkg.R
+.#buildPkg.R
 .gitignore
 .Rprofile
 ^\.travis\.yml$
diff --git a/R/legTools.R b/R/legTools.R
index 84f24243c705bc42aeb58ba4f36fe1872655c4a0..ce6b7850ae83e2328015a5ffb49c19afbff4507f 100644
--- a/R/legTools.R
+++ b/R/legTools.R
@@ -32,7 +32,7 @@ NULL
 #' @format a \code{data.frame} with 20 records and 2 variables.
 #'
 #' @source Frederico, P. (2009). Curso de Estatística Experimental
-#' (15th ed.). Piracicaba, São Paulo: FEALQ.
+#' (15th ed.). Piracicaba, São Paulo: FEALQ. (page 62)
 #'
 #' @examples
 #'
@@ -81,3 +81,42 @@ NULL
 #'      xlab="Variety")
 #'
 NULL
+
+#' @name plowing
+#'
+#' @title Plowing level on corn yield
+#'
+#' @description These data are from an experiment done by the engineer
+#' Duvilio Ometto to study the effect of plowing level on corn yield. It
+#' was used 2 levels of plowing: normal (or superficial) and deep. The
+#' experiment was done in a randomized complete block design with 6
+#' blocks. Corn yield (t ha^{-1}) was recorded in each experimental unit
+#' but in this experiment there was 2 experimental units for each factor
+#' level in each block.
+#'
+#' \itemize{
+#'     \item block a categorical unordered factor with 6 levels.
+#'     \item plow a categorical unordered factor with 2 levels.
+#'     \item yield corn yield (kg in 200 m^{2} of area).
+#' }
+#'
+#' @docType data
+#'
+#' @keywords datasets
+#'
+#' @usage data(plowing)
+#'
+#' @format a \code{data.frame} with 24 records and 3 variables.
+#'
+#' @source Frederico, P. (2009). Curso de Estatística Experimental
+#' (15th ed.). Piracicaba, São Paulo: FEALQ. (page 91)
+#'
+#' @examples
+#' require(lattice)
+#' data(potatoyield)
+#'
+#' xyplot(yield~plow|block, data=plowing, type=c("p", "a"),
+#'        ylab=expression(Yield~(t~ha^{-1})),
+#'        xlab="Plowing level")
+#'
+NULL
diff --git a/man/plowing.Rd b/man/plowing.Rd
new file mode 100644
index 0000000000000000000000000000000000000000..267999b1fd5e051b04b6dc0f5c43def5b9ac69ee
--- /dev/null
+++ b/man/plowing.Rd
@@ -0,0 +1,39 @@
+% Generated by roxygen2 (4.1.1): do not edit by hand
+% Please edit documentation in R/legTools.R
+\docType{data}
+\name{plowing}
+\alias{plowing}
+\title{Plowing level on corn yield}
+\format{a \code{data.frame} with 24 records and 3 variables.}
+\source{
+Frederico, P. (2009). Curso de Estatística Experimental
+(15th ed.). Piracicaba, São Paulo: FEALQ. (page 91)
+}
+\usage{
+data(plowing)
+}
+\description{
+These data are from an experiment done by the engineer
+Duvilio Ometto to study the effect of plowing level on corn yield. It
+was used 2 levels of plowing: normal (or superficial) and deep. The
+experiment was done in a randomized complete block design with 6
+blocks. Corn yield (t ha^{-1}) was recorded in each experimental unit
+but in this experiment there was 2 experimental units for each factor
+level in each block.
+
+\itemize{
+    \item block a categorical unordered factor with 6 levels.
+    \item plow a categorical unordered factor with 2 levels.
+    \item yield corn yield (kg in 200 m^{2} of area).
+}
+}
+\examples{
+require(lattice)
+data(potatoyield)
+
+xyplot(yield~plow|block, data=plowing, type=c("p", "a"),
+       ylab=expression(Yield~(t~ha^{-1})),
+       xlab="Plowing level")
+}
+\keyword{datasets}
+
diff --git a/man/wgpigs.Rd b/man/wgpigs.Rd
index 20a2cfac9ccd141712bc28dcf7c4c43e60854ec4..afe00d31be83e4671ac0b9233010c5c202e90432 100644
--- a/man/wgpigs.Rd
+++ b/man/wgpigs.Rd
@@ -7,7 +7,7 @@
 \format{a \code{data.frame} with 20 records and 2 variables.}
 \source{
 Frederico, P. (2009). Curso de Estatística Experimental
-(15th ed.). Piracicaba, São Paulo: FEALQ.
+(15th ed.). Piracicaba, São Paulo: FEALQ. (page 62)
 }
 \usage{
 data(wgpigs)