On my set up at least:
shift + alt gr ' <vowel>: áéíóú
shitf + alt gr ` <vowel>: àèìòù
shift + alt gr - <vowel>: āēīōū
On my set up at least:
shift + alt gr ' <vowel>: áéíóú
shitf + alt gr ` <vowel>: àèìòù
shift + alt gr - <vowel>: āēīōū