| Reference | Title of publication | Public |
Bartels & Boomsma (2009): study NL 2005
| Born to be Happy? The Etiology of Subjective Well-Being.
| 12+aged, mono- and dizygotic twins and their non-twin sibblings, The Netherlands, 2005-2007
|
Emde et al. (1992): study US Colorado 1986
| Temperament, Emotion, and Cognition at Fourteen Months: The MacArthur Longitudinal Twin Study
| 14 months aged, same-sex twin pairs, Colorado, United States, 1986-1989
|
Kohler et al. (2005): study DK 2002
| Partner + Children = Happiness? The Effects of Partnerships and Fertility on Well-Being.
| 20-70 aged identical twins, Denmark, 2002
|
Koivumaa-Honkanen et al. (2003): study FI 1976
| Self-Reported Happiness in Life and Suicide in Ensuing 20 Years.
| Adults, Finland, 1976-1995
|
Loehlin & Nichols (1976): study US 1963
| Heredity, Environment and Personality. A Study of 850 Sets of Twins.
| Adolescent same-sex twins, USA, 1963
|
Plomin et al. (1993): study US Colorado 1986
| Genetic change and continuity from fourteen to twenty months: The MacArthur Longitudinal Twin Study
| Same-sex twins, Colorado, United States, followed from 14 to 20 months, 1986-1989
|
Robinson et al. (2001): study US 1986
| Dispositional Cheerfullness. Early Genetic and Environmental Influences.
| Toddlers, same-sex twins, Colorado, United States, followed from 14 to 24 months of age, 1986-1989
|