Key points are not available for this paper at this time.
Mary Main, Donna R. Weston, The Quality of the Toddler's Relationship to Mother and to Father: Related to Conflict Behavior and the Readiness to Establish New Relationships, Child Development, Vol. 52, No. 3 (Sep., 1981), pp. 932-940
Main et al. (Tue,) studied this question.