C# ListBox from a lists of lists of objects (and deeper)

namespace mySillyExample
{
  public class BookShelf
  {
    public Shelf[] myShelves{get; set;}
  }

  public class Shelf
  {
    public Book[] booksOnThisShelf{get; set;}
  }

  public class Book
  {
    public string Title {get; set;};
    public string Author{get; set;};
    public string ISBN {get; set;};
  }
}

<ListBox Height="154" HorizontalAlignment="Left"
         ItemsSource="{Binding Path=BookShelf.myShelves}"
         Margin="171,475,0,0" VerticalAlignment="Top" Width="333" >
  <ListBox.ItemTemplate>
    <DataTemplate>
      <TextBlock Text="{Binding Path=booksOnThisShelf.[0].Title}" />
    </DataTemplate>
  <ListBox.ItemTemplate>
</ListBox>

//ViewModelBase should be a base class that implements INotifyPropertyChanged
public class MyViewModel : ViewModelBase
{
     public readonly IDataProvider _provider;

     public MyViewModel(IDataProvider provider)
     {
         _provider = provider ?? (some default provider);
     }

     public IList<String> Titles
     {
         get
         {
              var q = from shelves in _provider.GetBookShelves()
                      from books in shelves.booksOnThisShelf
                      select books.Title;

              return q as List<String>;
         }
     }
}