Complex sentence: Christie wrote more Poirot stories than any of the others, even though she thought the character to be "rather insufferable"; following his death in the 1975 novel "Curtain" his obituary appeared on the front page of "The New York Times".
Split into simpler sentences: Christie wrote more Poirot stories than any of the others, even though she thought the character to be "rather insufferable". Following the publication of the 1975 novel "Curtain", Poirot's obituary appeared on the front page of "The New York Times".