/// <summary>Initializes a new instance of the <see cref="AtomPubCollection"/> class with the specified title and href.</summary>
 /// <param name="title">A <see cref="string"/> representing the title of the collection.</param>
 /// <param name="href">A <see cref="string"/> representing the href of the collection.</param>
 /// <exception cref="ArgumentNullException"><paramref name="title"/> or <paramref name="href"/> is null.</exception>
 /// <exception cref="ArgumentException"><paramref name="href"/> is an empty <see cref="string"/>.</exception>
 public AtomPubCollection(AtomTitle title, string href)
 {
   if(title == null) throw new ArgumentNullException("title");
   if(href == null) throw new ArgumentNullException("href");
   if(href == "") throw new ArgumentException(Errors.EmptyString, "href");
   this.Title = title;
   this.Href = href;
 }
 /// <summary>Initializes a new instance of the <see cref="AtomPubWorkspace"/> class with the specified title.</summary>
 /// <param name="title">A <see cref="string"/> representing the title of the workspace.</param>
 public AtomPubWorkspace(AtomTitle title)
 {
   if(title == null) throw new ArgumentNullException("title");
   this.Title = title;
 }