The objective of this article is to analyze scientific networks using publications as activators and marks of relationships between researchers. The social networks mobilized by authors in their publications through bibliographic references are defined as citational circles which gather a lot of different relationships : both social and intellectual, personal and professional, individual and collective. The study of 1410 references through 32 articles of chemistry and interviews with their main author highlights four types of citational circles. These circles involve four type of sociability : reading and surveillance ; discussion and confrontation ; collaboration and contrast ; competition and rivalry. Each of them refers to specific practices and dynamics : teamwork, international context of research, emergence or sustainability of thematic, etc.