ðiːz fˈiːtʃɚz ɑːɹ dˈɑːkjuːməntᵻd ɪn vˈɛɹiəs bˈʊks baɪ kɹˈɪs ˈɛbz ænd hɐvbɪn ɛksplˈoːɹd baɪ ðə ɡɹˈoʊvənɚ kˈeɪvɪŋ klˈʌb.
These features are documented in various books by Cris Ebbs and have been explored by the Grosvenor Caving Club.