Abstract: Retainers and a binder assembly including the retainers are provided for detachably mounting publications having double leaves with folds intermediate their edges and the binder having two spaced fastener members. Each retainer has an elongated rod section, a u-shaped section at each end with distal portions extending toward each other, and a loop defined on each distal end portion and spaced apart to register with the spaced fastener members, thus to detachably mount publication leaves on the retainers by introduction of respective retainers between the leaves of respective groups to retain the group of leaves on the retainer by engagement of the retainer with said folds.