Sorry in advance if the papers will be of no use for you for they do not belong to authors you've mentioned, but there are some data on Cyperaceae mycorrhizas.
Dear Eduardo, in my recent article "Diversity of arbuscular mycorrhizal fungi (Glomeromycota) in maritime sand dunes of Brazilian northeast" I found some species of AMF in the rhizosphere of two species of Cyperaceae (Cyperus maritimus and Cyperus sp.1)! I also know the article "Mycorrhiza in sedges—an overview' (Muthukumar et al), published in Mycorrhiza, but the date is 2004! Best regards!