update addressing section

website/docs/internals/resource-addressing.html.markdown

@@ -16,7 +16,7 @@ larger infrastructure. An address is made up of two parts:
 [module path][resource spec]
 ```
 
-__Module path__:
+## Module path
 
 A module path addresses a module within the tree of modules. It takes the form:
 
@@ -27,8 +27,8 @@ module.module_name[module index]
  * `module` - Module keyword indicating a child module (non-root). Multiple `module`
    keywords in a path indicate nesting.
  * `module_name` - User-defined name of the module.
- * `[module index]` - (Optional) Index into a module with multiple
-   instances, surrounded by square brace characters (`[` and `]`).
+ * `[module index]` - (Optional) [Index](#index-values-for-modules-and-resources) into a
+   module with multiple instances, surrounded by square brace characters (`[` and `]`).
 
 An address without a resource spec, i.e. `module.foo` applies to every resource within
 the module if a single module, or all instances of a module if a module has multiple instances.
@@ -37,10 +37,16 @@ such as `module.foo[0]`.
 
 If the module path is omitted, the address applies to the root module.
 
+An example of the `module` keyword delineating between two modules that have multiple instances:
+
+```
+module.foo[0].module.bar["a"]
+```
+
 -> Module index only applies to modules in Terraform v0.13 or later, as in earlier
 versions of Terraform, a module could not have multiple instances.
 
-__Resource spec__:
+## Resource spec
 
 A resource spec addresses a specific resource in the config. It takes the form:
 
@@ -50,15 +56,15 @@ resource_type.resource_name[resource index]
 
  * `resource_type` - Type of the resource being addressed.
  * `resource_name` - User-defined name of the resource.
- * `[resource index]` - (Optional) Index into a resource with multiple
-   instances, surrounded by square brace characters (`[` and `]`).
+ * `[resource index]` - (Optional) [Index](#index-values-for-modules-and-resources)
+   into a resource with multiple instances, surrounded by square brace characters (`[` and `]`).
 
 -> In Terraform v0.12 and later, a resource spec without a module path prefix
 matches only resources in the root module. In earlier versions, a resource spec
 without a module path prefix will match resources with the same type and name
 in any descendent module.
 
-__Index values for Modules and Resources__:
+## Index values for Modules and Resources
 
 The following specifications apply to index values on modules and resources with multiple instances: