| Christianity and paganism, 350-750 : the conversion of western Europe | Hillgarth, J. N. | Monograph or Collective Volume | [s.n.] | 1986 |
| Ireland and Spain in the seventh century | Hillgarth, J. N. | Article in Journal | | 1984 |
| Modes of evangelization of western Europe in the seventh century | Hillgarth, J. N. | Article in Book | | 1987 |
| Old Ireland and Visigothic Spain | Hillgarth, J. N. | Article in Book | | 1965 |
| The East, Visigothic Spain and the Irish | Hillgarth, J. N. | Article in Book | | 1961 |
| The position of Isidorian studies : a critical review of the literature, 1936-75 | Hillgarth, J. N. | Article in Journal | | 1983 |
| The seventh century change and continuity : proceedings of a joint French and British colloquium held at the Warburg Institute 8-9 July 1988 | | Monograph or Collective Volume | Warburg Institute | 1992 |
| Visigothic Spain and early Christian Ireland | Hillgarth, J. N. | Article in Journal | | 1962 |