using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace Entities { public class BookEntity { public int ID { get; set; } public string Title { get; set; } public string Author { get; set; } public string Isbn { get; set; } public PersonEntity? Person { get; set; } public BookEntity(string title, string author, string isbn) { Title = title; Author = author; Isbn = isbn; } } }