This triologism emerges from Seamus Heaney’s imagining how Philip Larkin would have written The Divine Comedy, triggered by his reading of Larkin’s poem ‘The Explosion’.

If Philip Larkin had ever composed his version of The Divine Comedy, he would probably have discovered himself not in a dark wood but in a railway tunnel half.way on a journey down to England.  His inferno proper migt have occurred before dawn, as a death-haunted aubade, whence he would have emerged into the lighted room inside the head of an old fool…

An ‘aubade’ is a poem or song intended to greet the dawn; the French word for ‘dawn’ is ‘aube’. 

Larkin’s poem can be seen here. 

Source: Seamus Heaney, Finders Keepers: Selected prose 1971-2001 (London: Faber and Faber, 2003), p. 151