// The path to the documents directory.
string dataDir = RunExamples.GetDataDir_NoteBook();
var notebook = new Notebook(dataDir + "test.onetoc2", new NotebookLoadOptions() { DeferredLoading = true });

notebook.LoadChildDocument(dataDir + "Aspose.one");  
notebook.LoadChildDocument(dataDir + "Locked Pass1.one", new LoadOptions() { DocumentPassword = "pass" });
notebook.LoadChildDocument(dataDir + "Locked Pass2.one", new LoadOptions() { DocumentPassword = "pass2" });