diff --git a/asdf.texinfo b/asdf.texinfo
index 981d7950d02a672c6a6f3c8c84d2815b4ebce277..4805b2a0057f81eb9d8848adab79f2bffa678b2f 100644
--- a/asdf.texinfo
+++ b/asdf.texinfo
@@ -337,7 +337,7 @@ option := :components component-list
         | :explain method-form
 	| :output-files  method-form
         | :operation-done-p method-form
-        | :depends-on ( {simple-component-name}* ) 
+        | :depends-on ( {dependency-def}* ) 
 	| :serial [ t | nil ]
         | :in-order-to ( {dependency}+ )
 
@@ -348,11 +348,18 @@ component-def  := simple-component-name
 
 component-type := :module | :file | :system | other-component-type
 
+dependency-def := simple-component-name
+               | ( :feature name )
+               | ( :version simple-component-name version-specifier)
+
 dependency := (dependent-op {requirement}+)
 requirement := (required-op {required-component}+)
              | (feature feature-name)
 dependent-op := operation-name
 required-op := operation-name | feature
+
+simple-component-name := string
+                      |  symbol
 @end verbatim
 
 @subsection Serial dependencies