diff --git a/dired.el b/dired.el
index 36c2f17..2ecd6bd 100644
--- a/dired.el
+++ b/dired.el
@@ -1143,19 +1143,21 @@ The return value is the target column for the file names."
             (forward-line)))))))

 (defun dired-internal-noselect (dir-or-list &optional switches mode)
-  ;; If DIR-OR-LIST is a string and there is an existing dired buffer
-  ;; for it, just leave buffer as it is (don't even call dired-revert).
-  ;; This saves time especially for deep trees or with ange-ftp.
-  ;; The user can type `g' easily, and it is more consistent with find-file.
-  ;; But if SWITCHES are given they are probably different from the
-  ;; buffer's old value, so call dired-sort-other, which does
-  ;; revert the buffer.
-  ;; Revert the buffer if DIR-OR-LIST is a cons or `dired-directory'
-  ;; is a cons and DIR-OR-LIST is a string.
-  ;; A pity we can't possibly do "Directory has changed - refresh? "
-  ;; like find-file does.
-  ;; Optional argument MODE is passed to dired-find-buffer-nocreate,
-  ;; see there.
+  "Internal function for `dired-noselect'.
+
+If DIR-OR-LIST is a string and there is an existing dired buffer
+for it, just leave buffer as it is (don't even call `dired-revert').
+This saves time especially for deep trees or with `ange-ftp'.
+The user can type `g' easily, and it is more consistent with `find-file'.
+But if SWITCHES are given they are probably different from the
+buffer's old value, so call `dired-sort-other', which does
+revert the buffer.
+Revert the buffer if DIR-OR-LIST is a cons or `dired-directory'
+is a cons and DIR-OR-LIST is a string.
+A pity we can't possibly do \"Directory has changed - refresh?\"
+like `find-file' does.
+Optional argument MODE is passed to `dired-find-buffer-nocreate',
+see there."
   (let* ((old-buf (current-buffer))
 	 (dirname (if (consp dir-or-list) (car dir-or-list) dir-or-list))
          (buffer (when (not (bound-and-true-p dired-allow-duplicate-buffers))
@@ -1219,20 +1221,24 @@ The return value is the target column for the file names."
     buffer))

 (defvar dired-buffers nil
-  ;; Enlarged by dired-advertise
-  ;; Queried by function dired-buffers-for-dir. When this detects a
-  ;; killed buffer, it is removed from this list.
-  "Alist of expanded directories and their associated Dired buffers.")
+  "Alist of expanded directories and their associated Dired buffers.
+The list is enlarged by `dired-advertise'. Function
+`dired-buffers-for-dir' queries this list and removes killed
+buffers from it, when detected.")

 (defvar dired-find-subdir)
+;; `dired-find-subdir' is defined in `dired-x.el'

 ;; FIXME add a doc-string, and document dired-x extensions.
 (defun dired-find-buffer-nocreate (dirname &optional mode)
-  ;; This differs from dired-buffers-for-dir in that it does not consider
-  ;; subdirs of default-directory and searches for the first match only.
-  ;; Also, the major mode must be MODE.
-  (if (and (featurep 'dired-x)
-           dired-find-subdir
+  "Internal function for `dired-internal-noselect'.
+Searches among buffers of major-mode MODE (default `dired-mode')
+for one visiting DIRNAME, and returns the first one found. This
+differs from `dired-buffers-for-dir' in that it does not consider
+subdirs of `default-directory', it searches only for the first
+match, and it can restrict its search to buffers of
+major-mode MODE."
+  (if (and (featurep 'dired-x) dired-find-subdir
            ;; Don't try to find a wildcard as a subdirectory.
 	   (string-equal dirname (file-name-directory dirname)))
       (let* ((cur-buf (current-buffer))