diff --git a/History.md b/History.md
index b00ad79e..ffd3d011 100644
--- a/History.md
+++ b/History.md
@@ -51,7 +51,7 @@ switch
 - *use validator in tests of library
 - *USt 0% wird aus invoice-klasse noch nicht sauber abgefangen
 - *ownContact sollte in einen Contact schreiben
-- new features additional docs, contract id, periods, corrected invoices, discounts
+- new features additional docs, contract id, periods, corrected invoices, discounts, occurrence dates and periods
 
 Mustangproject 1.7.8
 =====
diff --git a/library/src/main/java/org/mustangproject/Invoice.java b/library/src/main/java/org/mustangproject/Invoice.java
index 22edf6b0..87720bc1 100644
--- a/library/src/main/java/org/mustangproject/Invoice.java
+++ b/library/src/main/java/org/mustangproject/Invoice.java
@@ -35,6 +35,9 @@ public class Invoice implements IExportableTransaction {
 	protected ArrayList<IZUGFeRDExportableItem> ZFItems = null;
 	protected String contractReferencedDocument = null;
 
+	protected Date occurrenceDateFrom = null;
+	protected Date occurrenceDateTo = null;
+
 	protected ArrayList<IZUGFeRDAllowanceCharge> Allowances = new ArrayList<IZUGFeRDAllowanceCharge>(),
 			Charges = new ArrayList<IZUGFeRDAllowanceCharge>(), LogisticsServiceCharges = new ArrayList<IZUGFeRDAllowanceCharge>();
 	protected IZUGFeRDTradeSettlement[] getTradeSettlement = null;
@@ -433,4 +436,41 @@ public class Invoice implements IExportableTransaction {
 		contractReferencedDocument=s;
 		return this;
 	}
+
+	public Invoice setOccurrenceDate(Date occur) {
+		occurrenceDateFrom=occur;
+		occurrenceDateTo=null;
+
+		return this;
+	}
+
+	public Invoice setOccurrencePeriod(Date start, Date end) {
+		occurrenceDateFrom=start;
+		occurrenceDateTo=end;
+
+		return this;
+	}
+
+	@Override
+	public Date getOccurrenceDate() {
+
+		return occurrenceDateFrom;
+	}
+
+	@Override
+	public Date getOccurrencePeriodFrom() {
+		if (occurrenceDateTo!=null)  {
+			return occurrenceDateFrom;
+		} else {
+			return null;
+		}
+	}
+	@Override
+	public Date getOccurrencePeriodTo() {
+		if (occurrenceDateTo!=null)  {
+			return occurrenceDateTo;
+		} else {
+			return null;
+		}
+	}
 }
diff --git a/library/src/main/java/org/mustangproject/ZUGFeRD/IExportableTransaction.java b/library/src/main/java/org/mustangproject/ZUGFeRD/IExportableTransaction.java
index 37b3970e..0d23f191 100644
--- a/library/src/main/java/org/mustangproject/ZUGFeRD/IExportableTransaction.java
+++ b/library/src/main/java/org/mustangproject/ZUGFeRD/IExportableTransaction.java
@@ -393,4 +393,15 @@ public interface IExportableTransaction {
 	default IZUGFeRDExportableContact getDeliveryAddress() {
 		return null;
 	}
+
+	default Date getOccurrenceDate() {
+		return null;
+	}
+
+	default Date getOccurrencePeriodFrom() {
+		return null;
+	}
+	default Date getOccurrencePeriodTo() {
+		return null;
+	}
 }
diff --git a/library/src/test/java/org/mustangproject/ZUGFeRD/ZF2PushTest.java b/library/src/test/java/org/mustangproject/ZUGFeRD/ZF2PushTest.java
index 1163bb3e..6d247848 100644
--- a/library/src/test/java/org/mustangproject/ZUGFeRD/ZF2PushTest.java
+++ b/library/src/test/java/org/mustangproject/ZUGFeRD/ZF2PushTest.java
@@ -178,7 +178,7 @@ public class ZF2PushTest extends TestCase {
 					 .setCreator(System.getProperty("user.name")).setZUGFeRDVersion(2).ignorePDFAErrors()
 					 .load(SOURCE_PDF)) {
 
-			ze.setTransaction(new Invoice().setCurrency("CHF").setDueDate(new Date()).setIssueDate(new Date()).setDeliveryDate(new Date()).setOwnOrganisationName(orgname).setOwnStreet("teststr").setOwnZIP("55232").setOwnLocation("teststadt").setOwnCountry("DE").setOwnTaxID("4711").setOwnVATID("0815").setRecipient(new Contact("Franz Müller", "0177123456", "fmueller@test.com", "teststr.12", "55232", "Entenhausen", "DE")).setNumber(number)
+			ze.setTransaction(new Invoice().setCurrency("CHF").setDueDate(new Date()).setOccurrenceDate(new Date()).setIssueDate(new Date()).setDeliveryDate(new Date()).setOwnOrganisationName(orgname).setOwnStreet("teststr").setOwnZIP("55232").setOwnLocation("teststadt").setOwnCountry("DE").setOwnTaxID("4711").setOwnVATID("0815").setRecipient(new Contact("Franz Müller", "0177123456", "fmueller@test.com", "teststr.12", "55232", "Entenhausen", "DE")).setNumber(number)
 					.addItem(new Item(new Product("Testprodukt", "", "C62", new BigDecimal(0)), amount, new BigDecimal(1.0)))
 					.addItem(new Item(new Product("Testprodukt", "", "C62", new BigDecimal(0)), amount, new BigDecimal(1.0)))
 					.addItem(new Item(new Product("Testprodukt", "", "C62", new BigDecimal(0)), amount, new BigDecimal(1.0)))
@@ -226,7 +226,7 @@ public class ZF2PushTest extends TestCase {
 					 .setCreator(System.getProperty("user.name")).setZUGFeRDVersion(2).ignorePDFAErrors()
 					 .load(SOURCE_PDF)) {
 
-			ze.setTransaction(new Invoice().setDueDate(new Date()).setIssueDate(new Date()).setDeliveryDate(new Date()).setOwnOrganisationName(orgname).setOwnStreet("teststr").setOwnZIP("55232").setOwnLocation("teststadt").setOwnCountry("DE").setOwnTaxID("4711").setOwnVATID("0815").setRecipient(new Contact("Franz Müller", "0177123456", "fmueller@test.com", "teststr.12", "55232", "Entenhausen", "DE")).setNumber(number)
+			ze.setTransaction(new Invoice().setDueDate(new Date()).setIssueDate(new Date()).setOccurrencePeriod(new Date(),new Date()).setDeliveryDate(new Date()).setOwnOrganisationName(orgname).setOwnStreet("teststr").setOwnZIP("55232").setOwnLocation("teststadt").setOwnCountry("DE").setOwnTaxID("4711").setOwnVATID("0815").setRecipient(new Contact("Franz Müller", "0177123456", "fmueller@test.com", "teststr.12", "55232", "Entenhausen", "DE")).setNumber(number)
 					.addItem(new Item(new Product("Testprodukt", "", "C62", new BigDecimal(0)), price, amount))
 					.addItem(new Item(new Product("Testprodukt", "", "C62", new BigDecimal(0)), price, amount))
 					.addItem(new Item(new Product("Testprodukt", "", "C62", new BigDecimal(0)), price, amount))