[1]Cnr syncs the node reference between two node types which have a nodereference to each other, so double editing nodes is no more needed. If one node has a reference the other node receives also a reference to the saved node if it is referenced in that node.
Drupal.org project page : http://drupal.org/project/cnr [2]
Drupalmodules.com : http://drupalmodules.com/module/corresponding-node-references [3]
Links
[1] https://dominiquedecooman.com/contribtion/drupal-module-corresponding-node-reference
[2] http://drupal.org/project/cnr
[3] http://drupalmodules.com/module/corresponding-node-references