2017 August 9, Raymond Hickey, “Irish English in the Anglophone world”, in World Englishes, volume 36, number 2:
Among the changes, which took place in Dublin English in the 1990s (Hickey 1999), are the following four which are also found in general forms of American English: (a) use of retroflex /r/, in fork [fo:ɻk]; (b) use of an intervocalic alveolar tap, for example in water [wɑɾɚ]; (c) the horse/hoarse‐merger and (d) the which/witch‐merger.