Poetry Ireland Presents a Reading. To mark the Sixtieth Birthday of John Montague and the Fiftieth Birthday of Seamus Heaney.  The Gate Theatre, Dublin 8 p.m., Sunday 11th June, 1989.  With Music by Liam O'Flynn. Contains:  'Hearth Song - for Seamus Heaney,' by John Montague and 'Fosterling - for John Montague,' by Seamus Heaney. Large card wrappers, fine copy.