Hopper 1995, pp. 32, 97, 231, 242, 245 Hopper, Keith (1995). Flann O'Brien: A Portrait of the Artist as a Young Post-Modernist. Cork: Cork University Press. ISBN978-1-85918-042-6. OCLC33189239.
Kenner 1997, pp. 61–71 Kenner, Hugh (1997). "The Fourth Policeman". In Clune, Anne; Hurson, Tess (eds.). Conjuring Complexities: Essays on Flann O'Brien. Belfast: Institute of Irish Studies. pp. 61–71. ISBN0-85389-675-5. OCLC37709678.
Kenner 1997, pp. 70–71 Kenner, Hugh (1997). "The Fourth Policeman". In Clune, Anne; Hurson, Tess (eds.). Conjuring Complexities: Essays on Flann O'Brien. Belfast: Institute of Irish Studies. pp. 61–71. ISBN0-85389-675-5. OCLC37709678.
Kenner 1997, p. 71 Kenner, Hugh (1997). "The Fourth Policeman". In Clune, Anne; Hurson, Tess (eds.). Conjuring Complexities: Essays on Flann O'Brien. Belfast: Institute of Irish Studies. pp. 61–71. ISBN0-85389-675-5. OCLC37709678.