public BooksViewModel(
     IBookFactService bookFactService,
     ILibraryDimService libraryDimService
     ) : base(bookFactService)
 {
     LibraryDimService = libraryDimService;
 }
 public BookFactController(IBookFactService bookFactService)
 {
     _bookFactService = bookFactService;
 }
 public FactController(IBookFactService bookFactService,
                       IAuthorFactService authorFactService)
 {
     _bookFactService   = bookFactService;
     _authorFactService = authorFactService;
 }