Two years later he published Cousas , and in 1929 he traveled to Brittany to study its stone crosses and publish As Cruces de Pedra na BretaÃ a. Two years , in 1926 , he published Cousas . He traveled to Brittany in 1928 to study stone crosses and publish As Cruces de Pedra na BretaÃ a. That is also the year when his only son dies at the age of 14 .