diff --git a/CSharp/Plugins/UniversalEditor.Plugins.Microsoft/DataFormats/Package/OpenPackagingConvention/OPCDataFormat.cs b/CSharp/Plugins/UniversalEditor.Plugins.Microsoft/DataFormats/Package/OpenPackagingConvention/OPCDataFormat.cs
index 71779515..838c6f42 100644
--- a/CSharp/Plugins/UniversalEditor.Plugins.Microsoft/DataFormats/Package/OpenPackagingConvention/OPCDataFormat.cs
+++ b/CSharp/Plugins/UniversalEditor.Plugins.Microsoft/DataFormats/Package/OpenPackagingConvention/OPCDataFormat.cs
@@ -46,7 +46,11 @@ namespace UniversalEditor.DataFormats.Package.OpenPackagingConvention
 					RelationshipsObjectModel rels = file.GetObjectModel<RelationshipsObjectModel>(new OPCRelationshipsDataFormat());
 					if (relatedFileName != null)
 					{
-
+						foreach (Relationship rel in rels.Relationships)
+						{
+							rel.Source = relatedFileName;
+							package.Relationships.Add(rel);
+						}
 					}
 					else
 					{
diff --git a/CSharp/Plugins/UniversalEditor.Plugins.Microsoft/ObjectModels/Package/PackageObjectModel.cs b/CSharp/Plugins/UniversalEditor.Plugins.Microsoft/ObjectModels/Package/PackageObjectModel.cs
index 1a8b4c13..fce239c6 100644
--- a/CSharp/Plugins/UniversalEditor.Plugins.Microsoft/ObjectModels/Package/PackageObjectModel.cs
+++ b/CSharp/Plugins/UniversalEditor.Plugins.Microsoft/ObjectModels/Package/PackageObjectModel.cs
@@ -41,10 +41,10 @@ namespace UniversalEditor.ObjectModels.Package
 		private FileSystemObjectModel mvarFileSystem = new FileSystemObjectModel();
 		public FileSystemObjectModel FileSystem { get { return mvarFileSystem; } }
 
-		public File[] GetFilesBySchema(string p)
+		public File[] GetFilesBySchema(string schema, string relationshipSource = null)
 		{
 			List<File> files = new List<File>();
-			Relationship[] rels = mvarRelationships.GetBySchema(p);
+			Relationship[] rels = mvarRelationships.GetBySchema(schema, relationshipSource);
 			foreach (Relationship rel in rels)
 			{
 				if (rel.Target.StartsWith("/"))
diff --git a/CSharp/Plugins/UniversalEditor.Plugins.Microsoft/ObjectModels/Package/Relationships/Relationship.cs b/CSharp/Plugins/UniversalEditor.Plugins.Microsoft/ObjectModels/Package/Relationships/Relationship.cs
index f1c989af..c70efc99 100644
--- a/CSharp/Plugins/UniversalEditor.Plugins.Microsoft/ObjectModels/Package/Relationships/Relationship.cs
+++ b/CSharp/Plugins/UniversalEditor.Plugins.Microsoft/ObjectModels/Package/Relationships/Relationship.cs
@@ -15,12 +15,15 @@ namespace UniversalEditor.ObjectModels.Package.Relationships
 			/// </summary>
 			/// <param name="schema">The schema to search for.</param>
 			/// <returns>Array of <see cref="Relationship" /> objects whose Schema property is set to the specified value.</returns>
-			public Relationship[] GetBySchema(string schema)
+			public Relationship[] GetBySchema(string schema, string source = null)
 			{
 				List<Relationship> rels = new List<Relationship>();
 				foreach (Relationship rel in this)
 				{
-					if (rel.Schema == schema) rels.Add(rel);
+					if (rel.Schema == schema && rel.Source == source)
+					{
+						rels.Add(rel);
+					}
 				}
 				return rels.ToArray();
 			}
@@ -35,11 +38,15 @@ namespace UniversalEditor.ObjectModels.Package.Relationships
 		private string mvarTarget = String.Empty;
 		public string Target { get { return mvarTarget; } set { mvarTarget = value; } }
 
+		private string mvarSource = null;
+		public string Source { get { return mvarSource; } set { mvarSource = value; } }
+
 		public object Clone()
 		{
 			Relationship clone = new Relationship();
 			clone.ID = (mvarID.Clone() as string);
 			clone.Schema = (mvarSchema.Clone() as string);
+			clone.Source = (mvarSource.Clone() as string);
 			clone.Target = (mvarTarget.Clone() as string);
 			return clone;
 		}