what's wrong in this procedure?

This error is returned Erro de SQL:

ERROR: column "Aguardando Pagto" does not exist at character 352 >>>

create or replace function get_historico() RETURNS SETOF twiste.type_cur__historico AS '

SELECT o.data_fim, sum(t.num_itens * t.valor) AS total, count(t.*) AS transacoes
FROM ofertas o
JOIN transacao t ON o.ofertas_id = t.ofertas_id
JOIN municipio m ON o.municipio_id = m.municipio_id
WHERE o.data_fim <= now() AND t.status IN("Aguardando Pagto", "Em análise", "Aprovado", "Completo")
GROUP BY o.data_fim;
'
language 'sql';

>> the column is t.status and not "Aguardando Pagto";
>> what's wrong ? thanks