diff --git a/man/cassavaYield.Rd b/man/cassavaYield.Rd
index 186defb34cb6dcf075fa1fe87ecfb4d728d8e937..9cf4bd0b4eff74c7971081c84602c284293c6049 100644
--- a/man/cassavaYield.Rd
+++ b/man/cassavaYield.Rd
@@ -28,7 +28,7 @@ These data are from an experiment done by The Brazilian
 }
 }
 \examples{
-require(lattice)
+library(lattice)
 data(cassavaYield)
 
 plot(yield~variety, data=cassavaYield,
diff --git a/man/plowing.Rd b/man/plowing.Rd
index 08bd7fde8c86c7ccafeb29b60ecf1c3c9a7dfa55..66fc799e3e867bf1900a1f18a2de5c528d62150e 100644
--- a/man/plowing.Rd
+++ b/man/plowing.Rd
@@ -28,7 +28,7 @@ These data are from an experiment done by the engineer
 }
 }
 \examples{
-require(lattice)
+library(lattice)
 data(potatoyield)
 
 xyplot(yield~plow|block, data=plowing, type=c("p", "a"),
diff --git a/man/potatoyield.Rd b/man/potatoyield.Rd
index c4579659b31aed480803e3b82e5d239d4191d544..441fce52b311a438c6aa1f1e765ccf9a585cdbe2 100644
--- a/man/potatoyield.Rd
+++ b/man/potatoyield.Rd
@@ -26,7 +26,7 @@ These data are from an experiment done by the engineer
 }
 }
 \examples{
-require(lattice)
+library(lattice)
 data(potatoyield)
 
 plot(yield~variety, data=potatoyield,
diff --git a/man/sugarcaneYield.Rd b/man/sugarcaneYield.Rd
index 6a6983f30e78d5cac0404f5bef182b165014f0df..a79e78b4eb9c57758b40d00368ec127201b9f603 100644
--- a/man/sugarcaneYield.Rd
+++ b/man/sugarcaneYield.Rd
@@ -26,7 +26,7 @@ These data are from an experiment done by The West São
 }
 }
 \examples{
-require(lattice)
+library(lattice)
 data(sugarcaneYield)
 
 plot(yield~variety, data=sugarcaneYield,
diff --git a/man/wgpigs.Rd b/man/wgpigs.Rd
index 0ffa7f43348166d621a14d2ed3f3d3bf854db82f..3fc9a3ee41e441766520f2385b24fb0e11bb5095 100644
--- a/man/wgpigs.Rd
+++ b/man/wgpigs.Rd
@@ -28,7 +28,7 @@ This is an artifial dataset corresponding a experiment
 }
 }
 \examples{
-require(lattice)
+library(lattice)
 data(wgpigs)
 
 xyplot(wg~ft, data=wgpigs,