Pengaruh kedekatan hubungan antara pemberi dan penerima tindakan baik terhadap kebahagiaan = The effect of closeness between giver and receiver act of kindness on happiness

Hubungan antara motivasi kerelawanan dan kebahagiaan pada emerging adulthood = The correlation between motivation to volunteer and happiness in emerging adulthood

Lebih baik sekarang daripada nanti: pengaruh waktu pemberian umpan balik dari penerima surat terima kasih terhadap kebahagiaan pengirim = Better now than later: the effect of delayed feedback from receiver of gratitude letter towards sender's happiness

The conquest of happiness

Stability of happiness : theories and evidence on whether happiness can change