Seems like in [comments](https://github.com/GoogleCloudPlatform/java-docs-samples/blob/master/firestore/src/main/java/com/example/firestore/snippets/References.java#L52-L53) should be "users", not "employees". [here too](https://github.com/GoogleCloudPlatform/java-docs-samples/blob/master/firestore/src/main/java/com/example/firestore/snippets/References.java#L65-L66) [Tutorial that reffers to this code](https://firebase.google.com/docs/firestore/data-model)