Platismatia glauca (L.) W.L. Culb. & C.F. Culb.
Large, foliose, glaucous to brownish lobes with erect, crisped, often isidiate or sorediate margins.Common on the branches of acid-barked trees
Smith et al. editors (2009) The Lichens of Great Britain and Ireland
Dobson (2018) Lichens: an Illustrated Guide to the British and Irish Species
Thell & Moberg, editors (2011) Nordic Lichen Flora, Volume 4: Parmeliaceae