diff --git a/pngset.c b/pngset.c
index cde4c6dad..667a02063 100644
--- a/pngset.c
+++ b/pngset.c
@@ -726,7 +726,7 @@ png_set_text_2(png_const_structrp png_ptr, png_inforp info_ptr,
          else
             max_text = INT_MAX;
 
-         /* Now allocate a new array and copy the old members in, this does all
+         /* Now allocate a new array and copy the old members in; this does all
           * the overflow checks.
           */
          new_text = png_voidcast(png_textp,png_realloc_array(png_ptr,
@@ -1020,8 +1020,8 @@ png_set_sPLT(png_const_structrp png_ptr,
 
       np->depth = entries->depth;
 
-      /* In the even of out-of-memory just return - there's no point keeping on
-       * trying to add sPLT chunks.
+      /* In the event of out-of-memory just return - there's no point keeping
+       * on trying to add sPLT chunks.
        */
       length = strlen(entries->name) + 1;
       np->name = png_voidcast(png_charp, png_malloc_base(png_ptr, length));
@@ -1032,8 +1032,8 @@ png_set_sPLT(png_const_structrp png_ptr,
       memcpy(np->name, entries->name, length);
 
       /* IMPORTANT: we have memory now that won't get freed if something else
-       * goes wrong, this code must free it.  png_malloc_array produces no
-       * warnings, use a png_chunk_report (below) if there is an error.
+       * goes wrong; this code must free it.  png_malloc_array produces no
+       * warnings; use a png_chunk_report (below) if there is an error.
        */
       np->entries = png_voidcast(png_sPLT_entryp, png_malloc_array(png_ptr,
           entries->nentries, sizeof (png_sPLT_entry)));
@@ -1072,7 +1072,7 @@ check_location(png_const_structrp png_ptr, int location)
    location &= (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT);
 
    /* New in 1.6.0; copy the location and check it.  This is an API
-    * change, previously the app had to use the
+    * change; previously the app had to use the
     * png_set_unknown_chunk_location API below for each chunk.
     */
    if (location == 0 && !(png_ptr->mode & PNG_IS_READ_STRUCT))
diff --git a/pngtrans.c b/pngtrans.c
index 9b6c3d0cd..631e3c15e 100644
--- a/pngtrans.c
+++ b/pngtrans.c
@@ -828,7 +828,7 @@ png_get_user_transform_ptr(png_const_structrp png_ptr)
 png_uint_32 PNGAPI
 png_get_current_row_number(png_const_structrp png_ptr)
 {
-   /* See the comments in png.h - this is the sub-image row when reading and
+   /* See the comments in png.h - this is the sub-image row when reading an
     * interlaced image.
     */
    if (png_ptr != NULL)
diff --git a/pngwio.c b/pngwio.c
index dfe8546ba..1b525f948 100644
--- a/pngwio.c
+++ b/pngwio.c
@@ -1,7 +1,7 @@
 
 /* pngwio.c - functions for data output
  *
- * Last changed in libpng 1.6.14 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.9 [February 6, 2014]
  * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)