js:
$('.js-fullcalendar').fullCalendar({
            header: {
                right: 'today',
                center: 'prev, title, next',
                left: ''
            },
            navLinks: true,
            editable: true,
            eventLimit: true,
            events: exhibitionList,
            eventColor: '#3279b7',
            columnFormat: 'dddd',
            eventRender: function(event, element) {
                if(event.logo){
                    element.find(".fc-title").prepend("<img class='fcalen__img' src="+event.logo+">").append("<span class='fcalen__city'>"+event.city+"</span>");
                }
            }
        });