diff --git a/types/sequelize/index.d.ts b/types/sequelize/index.d.ts
index b7bf448aed..dae8b3475c 100644
--- a/types/sequelize/index.d.ts
+++ b/types/sequelize/index.d.ts
@@ -7,6 +7,7 @@
 //                 Patsakol Tangjitcharoenchai <https://github.com/kukoo1>
 //                 Sebastien Bramille <https://github.com/oktapodia>
 //                 Nick Mueller <https://github.com/morpheusxaut>
+//                 Philippe D'Alva <https://github.com/TitaneBoy>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 // TypeScript Version: 2.3
 
@@ -1329,7 +1330,13 @@ declare namespace sequelize {
          * A string or a data type to represent the identifier in the table
          */
         keyType?: DataTypeAbstract;
-
+        /**
+         * A string to represent the name of the field to use as the key for an 1 to many association in the source table. 
+         * 
+         * @see http://docs.sequelizejs.com/class/lib/model.js~Model.html#static-method-hasMany
+         * @see https://github.com/sequelize/sequelize/blob/b4fd46426db9cdbb97074bea121203d565e4195d/lib/associations/has-many.js#L81
+         */
+        sourceKey?: string;
     }
 
     /**