function eml(email){

	if (document.group_form.name.value == ""){
	window.alert("Please, insert your name");
	document.group_form.name.focus();
	go = false;
	}

	if (document.group_form.surname.value == ""){
	window.alert("Please, insert your surname");
	document.group_form.surname.focus();
	go = false;
	}

	if (document.group_form.street.value == ""){
	window.alert("Please, insert your street and number");
	document.group_form.street.focus();
	go = false;
	}

	if (document.group_form.city.value == ""){
	window.alert("Please, insert your city");
	document.group_form.city.focus();
	go = false;
	}

	if (document.group_form.zip.value == ""){
	window.alert("Please, insert your ZIP Code");
	document.group_form.zip.focus();
	go = false;
	}

	if (document.group_form.country.value == ""){
	window.alert("Please, insert your country");
	document.group_form.country.focus();
	go = false;
	}

	if (document.group_form.phone.value == ""){
	window.alert("Please, insert your phone number");
	document.group_form.phone.focus();
	go = false;
	}

    if (document.group_form.email.value == ""){
	window.alert("Please, enter your email");
	document.group_form.email.focus();
	go = false;
	}

	if (document.group_form.doa_day.value == ""){
	window.alert("Please, enter date of arrival");
	document.group_form.doa_day.focus();
	go = false;
	}

	if (document.group_form.nights.value == ""){
	window.alert("Please, enter number of nights");
	document.group_form.nights.focus();
	go = false;
	}

	if (document.group_form.n_people.value == ""){
	window.alert("Please, enter number of people");
	document.group_form.n_people.focus();
	go = false;
	}

	if (document.group_form.room_type.value == ""){
	window.alert("Please, enter room type");
	document.group_form.room_type.focus();
	go = false;
	}

	if (document.group_form.n_room.value == ""){
	window.alert("Please, enter number of rooms");
	document.group_form.n_room.focus();
	go = false;
	}

	if (document.group_form.p_type_hotel.value == ""){
	window.alert("Please, select your preferred hotels");
	document.group_form.p_type_hotel.focus();
	go = false;
	}

	else if (email.indexOf("@")<1 || email.indexOf(".")<1 || email.indexOf(" ")>1){
	window.alert("Your email is invalid. Please, enter your valid email");
	document.group_form.email.focus();
	go = false;
	}

	else go = true;
}