+-------------+               +-------------+               +-------------+ 
 | person_role |               | admin_c     |               | last        | 
 +-------------+        1      +-------------+        N    n +-------------+ 
 | pe_ro_id    o--------}-+  M | object_id   o--------}-+--}-o serial      | 
 | is_person   |          +--}-o pe_ro_id    |          |    | prev_serial | 
 |*nic_hdl     |          |    | object_type |          |    | object      | 
 +-------------+          |    | ref_type    |          |    +-------------+ 
                          |    +-------------+          |
                          |                             |
 +----------+             |    +-----------+            |                    
 | names    |             |    | li_author |            |                    
 +----------+           m |    +-----------+          N |                    
 | pe_ro_id o-----------}-+  M | li_id     o----------}-+                    
 |*name     |             +--}-o pe_ro_id  |            |                    
 +----------+             |    | ref_type  |            |                    
                          |    +-----------+            |                    
 +----------+             |                             |                    
 | junk     |             |    +-------------+          |                    
 +----------+           1 |    | tech_c      |          |                    
 | id       o-----------}-+    +-------------+        N |                    
 | junk_key |             |  M | object_id   o--------}-+                    
 +----------+             |--}-o pe_ro_id    |          |                    
                          |    | object_type |          |                    
                          |    | ref_type    |          |                    
                          |    +-------------+          |                    
                          |                             |                    
                          |    +-------------+          |                    
                          |    | zone_c      |          |                    
                          |    +-------------+        N |                    
                          |  M | object_id   o--------}-+                    
                          +--}-o pe_ro_id    |                               
                               | object_type |           
                               | ref_type    |                               
                               +-------------+