//^[a-z\u00C0-\u02AB'´`]+\.?\s([a-z\u00C0-\u02AB'´`]+\.?\s?)+$

function isValidName(myval) {
    var validCharactersRegex = /^[a-z\u00C0-\u02AB'´`]+\.?\s([a-z\u00C0-\u02AB'´`]+\.?\s?)+$/;
 
    return validCharactersRegex.test(myval.trim());
}