Possible Clues:

• ''The Lake Isle of Innisfree'' poet
• Irish poet who wrote 'The Lake Isle of Innisfree'
• The old are on the way up, he wrote
• "The Land of Heart's Desire" playwright
• He wrote 'It's certain that fine women eat / A crazy salad with their meat'
• Irish poet (The Winding Stair)
• Poet who wrote 54-Down
• W B . . . . ., great Irish poet
• W B - - , poet
• W.B. - - , poet