Dewitte, M., & De Houwer, J. (2008), Proximity and distance motives in adult attachment. European Journal of Personality, 22, 675-694
Lisa M. Diamond, Angela M. Hicks, and Kimberly D. Otter-Henderson, (2008), Every Time You Go Away: Changes in Affect, Behavior, and Physiology Associated With Travel-Related Separations from Romantic Partners, Journal of Personality and Social Psychology, Vol. 95, No. 2, 385-403
Gaine, G. S. and La Guardia, J. G. (2009), The contributions of motivations to maintain a relationship and motivations toward relational activities to relationship well-being, Department of Psychology, University of Waterloo, Motivation and Emotion, 33, 184-202.