diff --git a/requirements.txt b/requirements.txt
index 757931f..bfe4f57 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,5 @@
 tornado==6.0.4
 isodate==0.6.0
 pytest==5.4.1
+schwifty==2020.11.0
+Cerberus==1.3.2
\ No newline at end of file
diff --git a/test_cerberus.py b/test_cerberus.py
new file mode 100644
index 0000000..803adbe
--- /dev/null
+++ b/test_cerberus.py
@@ -0,0 +1,38 @@
+#!/usr/bin/python3
+
+import cerberus
+from schwifty import IBAN, BIC
+import datetime
+
+def valid_iban(field, value, error):
+    try:
+        IBAN(value)
+        return True
+    except ValueError:
+        error(field, 'not a valid IBAN')
+
+def valid_bic(field, value, error):
+    try:
+        BIC(value)
+        return True
+    except ValueError:
+        error(field, 'not a valid BIC')
+
+def iso_date(field, value, error):
+    try:
+        datetime.datetime.strptime(value, "%Y-%m-%d")
+        return True
+    except ValueError:
+        error(field, 'not a valid IDO 8601 date')
+
+document = {'finanzdaten': {'bic': 'BELADEBEXXX', 'holder': '', 'iban': 'DE68100500004164690823', 'issuance': '2013-02-12', 'reference': '0023', 'scan-sepa-mandate': ''}, 'mitgliederdaten': {'bis': '', 'mitgliedsbeitrag': '30', 'scan-antrag': '', 'schliessberechtigung': 'Ja', 'spendenbeitrag': '', 'status': 'V', 'von': '2012-05-06'}, 'stammdaten': {'address_code': '39106', 'address_country': 'DE', 'address_label': 'David Kilias\nHohepfortestr. 9\n39106 Magdeburg', 'address_locality': 'Magdeburg', 'address_region': '', 'address_street': 'Hohepfortestr. 9', 'birth_date': '1986-11-29', 'birth_location': 'Karl-Marx-Stadt', 'email': 'david.kilias@netz39.de', 'fullname': 'David Kilias', 'nickname': 'dkdent', 'pgp-key': '', 'ssh-key': ''}, 'timestamp': '2020-03-25T23:58:11', 'id': '6af68'}
+
+schema_fin={'bic': {'type': 'string', 'check_with': valid_bic},
+            'iban': {'type': 'string', 'check_with': valid_iban},
+            'issuance': {'type': 'string', 'check_with': iso_date},
+            'reference': {'type': 'string'},
+            'scan-sepa-mandate': {'type': 'string'},
+            'holder': {'type': 'string'}}
+
+v = cerberus.Validator()
+v.validate(document['finanzdaten'], schema_fin)
\ No newline at end of file