diff --git a/DESCRIPTION b/DESCRIPTION
index e7d6924..c8c30cc 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -2,7 +2,7 @@ Package: seriation
 Type: Package
 Title: Infrastructure for Ordering Objects Using Seriation
 Version: 1.5.6
-Date: 2024-08-13
+Date: 2024-08-19
 Authors@R: c(
 	person("Michael", "Hahsler", role = c("aut", "cre", "cph"),
 	  email = "mhahsler@lyle.smu.edu",
diff --git a/NEWS.md b/NEWS.md
index 453ef76..f887b75 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,4 +1,4 @@
-# seriation 1.5.6 (08/13/2024)
+# seriation 1.5.6 (08/19/2024)
 
 ## New Features
 - Added registered_by field to registries. 
@@ -7,6 +7,7 @@
 - We replaced the FORTRAN implementation for BEA with code from package TSP.
 - ME is now calculated using C code.
 - optimal.c: updated memory allocation to R allocation.
+- stress.c: updated memory allocation to R allocation.
 
 ## Bug Fixes
 - Added two missing package anchors to palette man page.
diff --git a/R/AAA_color_palette.R b/R/AAA_color_palette.R
index aa37f44..2dd46c1 100644
--- a/R/AAA_color_palette.R
+++ b/R/AAA_color_palette.R
@@ -30,7 +30,7 @@
 #' The two diverging palettes are: `bluered()` and `greenred()`.
 #'
 #' @name palette
-#' @aliases palette, colors
+#' @aliases palette colors
 #' @family plots
 #'
 #' @param n number of different colors produces.
diff --git a/R/AAA_seriation-package.R b/R/AAA_seriation-package.R
index 36dad8b..06331e5 100644
--- a/R/AAA_seriation-package.R
+++ b/R/AAA_seriation-package.R
@@ -4,9 +4,9 @@
 #' - Seriation: [seriate()], [criterion()], [get_order()], [permute()]
 #' - Visualization: [pimage()], [bertinplot()], [hmap()], [dissplot()], [VAT()]
 #'
-#' @section Available seriation methods:
+#' @section Available seriation methods and criteria:
 #' * [A list with the implemented seriation methods](https://mhahsler.github.io/seriation/seriation_methods.html)
-#' * [A visual comparison between seriation methods](https://mhahsler.github.io/seriation/visual_comparison.html)
+#' * [A visual comparison between seriation methods](https://mhahsler.github.io/seriation/comparison.html)
 #' * [A list with the implemented seriation criteria](https://mhahsler.github.io/seriation/seriation_criteria.html)
 #'
 #' @section Quickstart guides:
diff --git a/man/palette.Rd b/man/palette.Rd
index 7179e6c..d736eb3 100644
--- a/man/palette.Rd
+++ b/man/palette.Rd
@@ -3,7 +3,6 @@
 \name{palette}
 \alias{palette}
 \alias{bluered}
-\alias{palette,}
 \alias{colors}
 \alias{greenred}
 \alias{reds}
diff --git a/man/seriation-package.Rd b/man/seriation-package.Rd
index f9f1c07..47477f4 100644
--- a/man/seriation-package.Rd
+++ b/man/seriation-package.Rd
@@ -16,11 +16,11 @@ Infrastructure for ordering objects with an implementation of several seriation/
 }
 }
 
-\section{Available seriation methods}{
+\section{Available seriation methods and criteria}{
 
 \itemize{
 \item \href{https://mhahsler.github.io/seriation/seriation_methods.html}{A list with the implemented seriation methods}
-\item \href{https://mhahsler.github.io/seriation/visual_comparison.html}{A visual comparison between seriation methods}
+\item \href{https://mhahsler.github.io/seriation/comparison.html}{A visual comparison between seriation methods}
 \item \href{https://mhahsler.github.io/seriation/seriation_criteria.html}{A list with the implemented seriation criteria}
 }
 }
diff --git a/src/stress.c b/src/stress.c
index de79f46..e53fddc 100644
--- a/src/stress.c
+++ b/src/stress.c
@@ -164,8 +164,8 @@ SEXP stress(SEXP R_x, SEXP R_r, SEXP R_c, SEXP R_type)
    * this sucks!
    */
 
-  r = Calloc(nr, int);
-  c = Calloc(nc, int);
+  r = R_Calloc(nr, int);
+  c = R_Calloc(nc, int);
 
   /* copy and shift indexes */
 
@@ -187,12 +187,12 @@ SEXP stress(SEXP R_x, SEXP R_r, SEXP R_c, SEXP R_type)
     [0] = stressNeumann(REAL(R_x), r, c, nr, nc, nrx);
     break;
   default:
-    Free(r);
-    Free(c);
+    R_Free(r);
+    R_Free(c);
     error("stress: type not implemented");
   }
-  Free(r);
-  Free(c);
+  R_Free(r);
+  R_Free(c);
 
   /* UNPROTECT(3); */
   UNPROTECT(1);
@@ -372,8 +372,8 @@ SEXP stress_dist(SEXP R_x, SEXP R_r, SEXP R_c, SEXP R_bycol, SEXP R_type)
    * this sucks!
    */
 
-  r = Calloc(nr, int);
-  c = Calloc(nc, int);
+  r = R_Calloc(nr, int);
+  c = R_Calloc(nc, int);
 
   /* copy and shift indexes */
 
@@ -388,7 +388,7 @@ SEXP stress_dist(SEXP R_x, SEXP R_r, SEXP R_c, SEXP R_bycol, SEXP R_type)
     PROTECT(R_obj = NEW_NUMERIC(nr * (nr - 1) / 2));
 
     d = REAL(R_obj);
-    t = Calloc(nr, double);
+    t = R_Calloc(nr, double);
 
     switch (INTEGER(R_type)[0])
     {
@@ -399,18 +399,18 @@ SEXP stress_dist(SEXP R_x, SEXP R_r, SEXP R_c, SEXP R_bycol, SEXP R_type)
       distNeumann(REAL(R_x), r, c, nr, nc, nrx, 1, d, t);
       break;
     default:
-      Free(r);
-      Free(c);
-      Free(t);
+      R_Free(r);
+      R_Free(c);
+      R_Free(t);
       error("stress_dist: \"type\" not implemented");
     }
-    Free(t);
+    R_Free(t);
     break;
   case 1:
     PROTECT(R_obj = NEW_NUMERIC(nc * (nc - 1) / 2));
 
     d = REAL(R_obj);
-    t = Calloc(nc, double);
+    t = R_Calloc(nc, double);
 
     switch (INTEGER(R_type)[0])
     {
@@ -421,20 +421,20 @@ SEXP stress_dist(SEXP R_x, SEXP R_r, SEXP R_c, SEXP R_bycol, SEXP R_type)
       distNeumann(REAL(R_x), c, r, nc, nr, 1, nrx, d, t);
       break;
     default:
-      Free(r);
-      Free(c);
-      Free(t);
+      R_Free(r);
+      R_Free(c);
+      R_Free(t);
       error("stress_dist: type not implemented");
     }
-    Free(t);
+    R_Free(t);
     break;
   default:
-    Free(r);
-    Free(c);
+    R_Free(r);
+    R_Free(c);
     error("stress_dist: \"bycol\" invalid");
   }
-  Free(r);
-  Free(c);
+  R_Free(r);
+  R_Free(c);
 
   /* UNPROTECT(3); */
   UNPROTECT(1);