Index: 01_system.html
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--- 01_system.html	(revision 1094)
+++ 01_system.html	(revision 1095)
@@ -41,7 +41,7 @@
 Attributes are simple, typically user defined key=value fields. Various
 tools in the toolchain may read and write different set of attributes.
 The meaning of most attributes is defined only by conventions. More
-about this can be found in chapter 2 (TODO: link).
+about attributes can be found in <a href="04_attrib.html">chapter 4.</a>
 
 
 <h3> 1.1.2. Cschem as a software package: sch-rnd </h3>