@Override
	public boolean equals(final Object obj) {
		if (this == obj) {
			return true;
		}
		if (obj == null) {
			return false;
		}
		if (!(obj instanceof Book)) {
			return false;
		}
		final Book other = (Book) obj;
		if (author == null) {
			if (other.author != null) {
				return false;
			}
		} else if (!author.equals(other.author)) {
			return false;
		}
		if (title == null) {
			if (other.title != null) {
				return false;
			}
		} else if (!title.equals(other.title)) {
			return false;
		}
		return true;
	}