function valida(f) {
	name_contact = document.getElementById("name_contact").value;
	if( name_contact == null || name_contact.length == 0 || /^\s+$/.test(name_contact) ) {
		alert("Ingrese un nombre v\u00E1lido");
		return false;
	}
	name_company = document.getElementById("name_company").value;
	if( name_company == null || name_company.length == 0 || /^\s+$/.test(name_company) ) {
		alert("Ingrese el nombre de la empresa");
		return false;
	}
	email_contact = document.getElementById("email_contact").value;
	if( email_contact.length != 0 ) {
		if( !(/\w{1,}[@][\w\-]{1,}([.]([\w\-]{1,})){1,3}$/.test(email_contact)) ) {
			alert("Ingrese un email v\u00E1lido");
			return false;
		}
	} else {
		alert("Ingrese un email v\u00E1lido");
		return false;
	}
	telephone_contact = document.getElementById("telephone_contact").value;
	if( telephone_contact == null || telephone_contact.length == 0 || /^\s+$/.test(telephone_contact) ) {
		alert("Ingrese un tel\u00E9fono v\u00E1lido");
		return false;
	}
}