match formatting in 06-params.md and link back

Author: mr-c

_episodes/13-expressions.md

@@ -86,30 +86,33 @@ Note that requirements must be provided as an array, with each entry (in this
 case, only `class: InlineJavascriptRequirement`) marked by a `-`. The same
 syntax is used to describe the additional command line arguments.
 
-You can only use expressions in certain fields.  These are:
-
-- [`arguments`](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandLineTool)
-- [`coresMin`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
-- [`coresMax`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
-- [`entry`](http://www.commonwl.org/v1.0/CommandLineTool.html#Dirent)
-- [`entryname`](http://www.commonwl.org/v1.0/CommandLineTool.html#Dirent)
-- `format` (in a [CommandInputParameter](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandInputParameter), [CommandOutputParamater](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandOutputParameter), [WorkflowOutputParameter](http://www.commonwl.org/v1.0/Workflow.html#WorkflowOutputParameter), or [ExpressionToolOutputParameter](http://www.commonwl.org/v1.0/Workflow.html#ExpressionToolOutputParameter))
-- [`expression`](http://www.commonwl.org/v1.0/Workflow.html#ExpressionTool)
-- [`envValue`](http://www.commonwl.org/v1.0/CommandLineTool.html#EnvironmentDef)
-- [`glob`](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandOutputBinding)
-- [`listing`](http://www.commonwl.org/v1.0/CommandLineTool.html#InitialWorkDirRequirement)
-- [`outdirMin`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
-- [`outdirMax`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
-- [`outputEval`](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandOutputBinding)
-- `secondaryFiles` (in a [CommandInputParameter](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandInputParameter), [CommandOutputParamater](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandOutputParameter), [WorkflowOutputParameter](http://www.commonwl.org/v1.0/Workflow.html#WorkflowOutputParameter), or [ExpressionToolOutputParameter](http://www.commonwl.org/v1.0/Workflow.html#ExpressionToolOutputParameter))
-- [`ramMin`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
-- [`ramMax`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
-- [`stdin`](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandLineTool)
-- [`stdout`](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandLineTool)
-- [`stderr`](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandLineTool)
-- [`tmpdirMin`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
-- [`tmpdirMax`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
-- `valueFrom` (in a [CommandLineBinding](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandLineBinding), or [WorkflowStepInput](http://www.commonwl.org/v1.0/Workflow.html#WorkflowStepInput))
+> ## Where are parameter references allowed?
+> Just like [parameter references]({{ page.root }}{% link _episodes/06-params.md %}), you can use JavaScript Expressions
+> only in certain fields.  These are:
+> 
+> - [`arguments`](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandLineTool)
+> - [`coresMin`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
+> - [`coresMax`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
+> - [`entry`](http://www.commonwl.org/v1.0/CommandLineTool.html#Dirent)
+> - [`entryname`](http://www.commonwl.org/v1.0/CommandLineTool.html#Dirent)
+> - `format` (in a [CommandInputParameter](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandInputParameter), [CommandOutputParamater](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandOutputParameter), [WorkflowOutputParameter](http://www.commonwl.org/v1.0/Workflow.html#WorkflowOutputParameter), or [ExpressionToolOutputParameter](http://www.commonwl.org/v1.0/Workflow.html#ExpressionToolOutputParameter))
+> - [`expression`](http://www.commonwl.org/v1.0/Workflow.html#ExpressionTool)
+> - [`envValue`](http://www.commonwl.org/v1.0/CommandLineTool.html#EnvironmentDef)
+> - [`glob`](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandOutputBinding)
+> - [`listing`](http://www.commonwl.org/v1.0/CommandLineTool.html#InitialWorkDirRequirement)
+> - [`outdirMin`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
+> - [`outdirMax`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
+> - [`outputEval`](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandOutputBinding)
+> - `secondaryFiles` (in a [CommandInputParameter](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandInputParameter), [CommandOutputParamater](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandOutputParameter), [WorkflowOutputParameter](http://www.commonwl.org/v1.0/Workflow.html#WorkflowOutputParameter), or [ExpressionToolOutputParameter](http://www.commonwl.org/v1.0/Workflow.html#ExpressionToolOutputParameter))
+> - [`ramMin`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
+> - [`ramMax`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
+> - [`stdin`](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandLineTool)
+> - [`stdout`](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandLineTool)
+> - [`stderr`](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandLineTool)
+> - [`tmpdirMin`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
+> - [`tmpdirMax`](http://www.commonwl.org/v1.0/CommandLineTool.html#ResourceRequirement)
+> - `valueFrom` (in a [CommandLineBinding](http://www.commonwl.org/v1.0/CommandLineTool.html#CommandLineBinding), or [WorkflowStepInput](http://www.commonwl.org/v1.0/Workflow.html#WorkflowStepInput))
+{: .callout }
 
 
 [file-prop]: http://www.commonwl.org/v1.0/CommandLineTool.html#File