https://www.drupaleasy.com/blogs/ultimike/2016/04/drupal-6-drupal-81x-custom-content-migration
https://thinkshout.com/blog/2017/05/skipping-a-version-migrating-from-drupal-6-to-drupal-8-with-drupal-migrate/
https://www.drupal.org/docs/8/upgrade/known-issues-when-upgrading-from-drupal-6-or-7-to-drupal-8
https://drupal.stackexchange.com/questions/164612/how-do-i-remove-a-configuration-object-from-the-active-configuration
https://www.metaltoad.com/blog/drupal-8-migrations-part-3-migrating-taxonomies-drupal-7
https://www.sitepoint.com/your-first-drupal-8-migration/
