Ìwé kan tó ń jẹ́ Engineering Happiness — A New Approach for Building a Joyful Life sọ pé : “ Tó o bá ń nífẹ̀ẹ́ àwọn èèyàn , ńṣe ni wọ́n á máa fi ìfẹ́ wá ẹ kiri . ”
Iwe kan to n je Engineering Happiness — A New Approach for Building a Joyful Life so pe : “ To o ba n nifee awon eeyan , nse ni won a maa fi ife wa e kiri . ”