code: public void insert(String firstName, String lastName, String number)
  	{
  		entries.add(new PhoneBookEntry(this, firstName, lastName, number));
  	}
docs: <p>insert.</p>
  
  @param firstName a {@link java.lang.String} object.
  @param lastName a {@link java.lang.String} object.
  @param number a {@link java.lang.String} object.