diff --git a/core/modules/migrate/src/Plugin/migrate/process/Callback.php b/core/modules/migrate/src/Plugin/migrate/process/Callback.php
index ad40b62..7e0bc24 100644
--- a/core/modules/migrate/src/Plugin/migrate/process/Callback.php
+++ b/core/modules/migrate/src/Plugin/migrate/process/Callback.php
@@ -20,6 +20,8 @@
  * arguments can be passed to the callback as this would make the migration YAML
  * file too complex.
  *
+ * @see https://www.drupal.org/node/2181783
+ *
  * @MigrateProcessPlugin(
  *   id = "callback"
  * )
diff --git a/core/modules/migrate/src/Plugin/migrate/process/Concat.php b/core/modules/migrate/src/Plugin/migrate/process/Concat.php
index 174818d..2fb14e5 100644
--- a/core/modules/migrate/src/Plugin/migrate/process/Concat.php
+++ b/core/modules/migrate/src/Plugin/migrate/process/Concat.php
@@ -15,6 +15,8 @@
 /**
  * Concatenates the strings in the current value.
  *
+ * @see https://www.drupal.org/node/2345927
+ *
  * @MigrateProcessPlugin(
  *   id = "concat",
  *   handle_multiples = TRUE
diff --git a/core/modules/migrate/src/Plugin/migrate/process/DedupeBase.php b/core/modules/migrate/src/Plugin/migrate/process/DedupeBase.php
index 8970bf8..dcb5cd3 100644
--- a/core/modules/migrate/src/Plugin/migrate/process/DedupeBase.php
+++ b/core/modules/migrate/src/Plugin/migrate/process/DedupeBase.php
@@ -20,6 +20,9 @@
  * creating filter format names, the current value is checked against the
  * existing filter format names and if it exists, a numeric postfix is added
  * and incremented until a unique value is created.
+ *
+ * @see https://www.drupal.org/node/2345929
+ *
  */
 abstract class DedupeBase extends ProcessPluginBase {
 
diff --git a/core/modules/migrate/src/Plugin/migrate/process/DedupeEntity.php b/core/modules/migrate/src/Plugin/migrate/process/DedupeEntity.php
index 175e9c9..34ec5a0 100644
--- a/core/modules/migrate/src/Plugin/migrate/process/DedupeEntity.php
+++ b/core/modules/migrate/src/Plugin/migrate/process/DedupeEntity.php
@@ -15,6 +15,8 @@
 /**
  * Ensures value is not duplicated against an entity field.
  *
+ * @see https://www.drupal.org/node/2135325
+ *
  * @MigrateProcessPlugin(
  *   id = "dedupe_entity"
  * )
diff --git a/core/modules/migrate/src/Plugin/migrate/process/DefaultValue.php b/core/modules/migrate/src/Plugin/migrate/process/DefaultValue.php
index 87f2b6f..4751830 100644
--- a/core/modules/migrate/src/Plugin/migrate/process/DefaultValue.php
+++ b/core/modules/migrate/src/Plugin/migrate/process/DefaultValue.php
@@ -14,6 +14,8 @@
 /**
  * This plugin sets missing values on the destination.
  *
+ * @see https://www.drupal.org/node/2135313
+ *
  * @MigrateProcessPlugin(
  *   id = "default_value"
  * )
diff --git a/core/modules/migrate/src/Plugin/migrate/process/Explode.php b/core/modules/migrate/src/Plugin/migrate/process/Explode.php
index 2fb4d00..156f971 100644
--- a/core/modules/migrate/src/Plugin/migrate/process/Explode.php
+++ b/core/modules/migrate/src/Plugin/migrate/process/Explode.php
@@ -15,6 +15,8 @@
 /**
  * This plugin explodes a delimited string into an array of values.
  *
+ * @see https://www.drupal.org/node/2674504
+ *
  * @MigrateProcessPlugin(
  *   id = "explode"
  * )
diff --git a/core/modules/migrate/src/Plugin/migrate/process/Get.php b/core/modules/migrate/src/Plugin/migrate/process/Get.php
index 5b720bc..f1aa267 100644
--- a/core/modules/migrate/src/Plugin/migrate/process/Get.php
+++ b/core/modules/migrate/src/Plugin/migrate/process/Get.php
@@ -14,6 +14,8 @@
 /**
  * This plugin copies from the source to the destination.
  *
+ * @see https://www.drupal.org/node/2135307
+ *
  * @MigrateProcessPlugin(
  *   id = "get"
  * )
diff --git a/core/modules/migrate/src/Plugin/migrate/process/MachineName.php b/core/modules/migrate/src/Plugin/migrate/process/MachineName.php
index 8f08dd6..237756e 100644
--- a/core/modules/migrate/src/Plugin/migrate/process/MachineName.php
+++ b/core/modules/migrate/src/Plugin/migrate/process/MachineName.php
@@ -22,6 +22,8 @@
  * and replaced by an underscore and multiple underscores are collapsed into
  * one.
  *
+ * @see https://www.drupal.org/node/2135323
+ *
  * @MigrateProcessPlugin(
  *   id = "machine_name"
  * )
diff --git a/core/modules/migrate/src/Plugin/migrate/process/Migration.php b/core/modules/migrate/src/Plugin/migrate/process/Migration.php
index 67f5a6a..e1bd7f2 100644
--- a/core/modules/migrate/src/Plugin/migrate/process/Migration.php
+++ b/core/modules/migrate/src/Plugin/migrate/process/Migration.php
@@ -20,6 +20,8 @@
 /**
  * Calculates the value of a property based on a previous migration.
  *
+ * @see https://www.drupal.org/node/2149801
+ *
  * @MigrateProcessPlugin(
  *   id = "migration"
  * )
diff --git a/core/modules/migrate/src/Plugin/migrate/process/SkipOnEmpty.php b/core/modules/migrate/src/Plugin/migrate/process/SkipOnEmpty.php
index 334d7eb..832ae1f 100644
--- a/core/modules/migrate/src/Plugin/migrate/process/SkipOnEmpty.php
+++ b/core/modules/migrate/src/Plugin/migrate/process/SkipOnEmpty.php
@@ -16,6 +16,8 @@
 /**
  * If the source evaluates to empty, we skip processing or the whole row.
  *
+ * @see https://www.drupal.org/node/2228793
+ *
  * @MigrateProcessPlugin(
  *   id = "skip_on_empty"
  * )
diff --git a/core/modules/migrate/src/Plugin/migrate/process/SkipRowIfNotSet.php b/core/modules/migrate/src/Plugin/migrate/process/SkipRowIfNotSet.php
index cc21e7c..8dbb5cd 100644
--- a/core/modules/migrate/src/Plugin/migrate/process/SkipRowIfNotSet.php
+++ b/core/modules/migrate/src/Plugin/migrate/process/SkipRowIfNotSet.php
@@ -15,6 +15,8 @@
 /**
  * If the source evaluates to empty, we skip the current row.
  *
+ * @see https://www.drupal.org/node/2345935
+ *
  * @MigrateProcessPlugin(
  *   id = "skip_row_if_not_set",
  *   handle_multiples = TRUE