Source: https://www.researchgate.net/profile/Margherita-Lanz/publication/231222897_Felt_obligation_and_the_family_life_cycle_A_study_on_intergenerational_relationships/links/5942943da6fdcc2515332a52/Felt-obligation-and-the-family-life-cycle-A-study-on-intergenerational-relationships.pdf