diff --git a/R/slopes.R b/R/slopes.R
index dd96fec..35e36c9 100644
--- a/R/slopes.R
+++ b/R/slopes.R
@@ -222,13 +222,13 @@ slope_matrices = function(m_xyz_split, fun = slope_matrix_weighted, ...) {
 #'   (rows representing linestrings) in the input object.
 #' @export
 #' @examples
+#' library(sf)
 #' routes = lisbon_road_network[1:3, ]
 #' dem = dem_lisbon_raster
 #' (s = slope_raster(routes, dem))
 #' cor(routes$Avg_Slope, s)
 #' slope_raster(routes, dem, directed = TRUE)
 #' # Demonstrate that reverse routes have the opposite directed slope
-#' library(sf)
 #' slope_raster(st_reverse(routes), dem, directed = TRUE)
 slope_raster = function(
   routes,
diff --git a/man/slope_raster.Rd b/man/slope_raster.Rd
index 5f19a63..bd284cb 100644
--- a/man/slope_raster.Rd
+++ b/man/slope_raster.Rd
@@ -58,12 +58,12 @@ geometries to \code{LINESTRING}s as follows:
 \code{r_linestring = sf::st_cast(routes, "LINESTRING")}.
 }
 \examples{
+library(sf)
 routes = lisbon_road_network[1:3, ]
 dem = dem_lisbon_raster
 (s = slope_raster(routes, dem))
 cor(routes$Avg_Slope, s)
 slope_raster(routes, dem, directed = TRUE)
 # Demonstrate that reverse routes have the opposite directed slope
-library(sf)
 slope_raster(st_reverse(routes), dem, directed = TRUE)
 }