namespace App.ViewModel
{
    public class BaseViewModel : INotifyPropertyChanged
    {
        public BaseViewModel()
        {
        }

        #region INotifyPropertyChanged Members

        public event PropertyChangedEventHandler PropertyChanged;

        #endregion

        protected void OnPropertyChanged(string propertyName)
        {
            PropertyChangedEventHandler handler = this.PropertyChanged;
            if (handler != null)
			{
                handler(this, new PropertyChangedEventArgs(propertyName));
			}

        }
    }
}

//usage
namespace App.ViewModel
{
    public class Book : BaseViewModel
    {

        public Book()
        {
        }

        private string author;
        public string Author
        {
            get
            {
                return this.author;
            }
            set
            {
                if (this.author != value)
                {
                    this.author = value;
		  //No need to write property change events as its in base class
                    this.OnPropertyChanged("Author");
                }
            }
        }

        private string title;
        public string Title
        {
            get
            {
                return this.title;
            }
            set
            {
                if (this.title != value)
                {
                    this.title = value;
                    this.OnPropertyChanged("Title");
                }
            }
        }

        private IEnumerable<Chapter> chapters;
        public IEnumerable<Chapter> Chapters
        {
            get
            {
                return this.chapters;
            }
            set
            {
                if (this.chapters != value)
                {
                    this.chapters = value;
                    this.OnPropertyChanged("Chapters");
                }
            }
        }

    }

}