i'm sorry i was lazy here's where i got the information about the diphthongal variants of and they make it clear in the references that wells a is wells j c accents of english an introduction cambridge cambridge university press they also say cruttenden is cruttenden a gimson's pronunciation of english th edn london arnold a handbook of varieties of english bernd kortmann edgar w schneider walter de gruyter is where i got the information about monophthongization in cockney they in turn referenced wells in this case wells refers to wells j c accents of english the british isles cambridge cambridge university press there you go