DOI Field - Publication Content Type

This is a New Mexico Customization that may be helpful to other EPSCoR jurisdictions.
A DOI (digital object identifier) was requested to be added locally here in New Mexico for the Publication Content Type.
Specifically, the DOI field was added upon a user selecting Journal Article as a Publication Type.
The logic below shows as not required as well as altered in the states function in the '/includes/' file.

Information -

--- a/includes/
+++ b/includes/
@@ -446,6 +446,13 @@ function er_form_er_publication_node_form_alter(&$form, &$form_state, $form_id){
'visible' => $published,
'required' => $published,
+ //Published
+ //Local NMEPSCoR DOI Field (not required) on "Published"
+ $form['field_er_publication_doi']['#states'] = array(
+ 'visible' => $published,
+ );