    .attr("class", "arrow")
    .attr("marker-end", "url(#edgeArrowhead)")
    .attr("x1", nodeSizeB)
    .attr("x2", nodeSizeB + nodeMargin + 14)
    .attr("y1", nodeSizeB / 2)
    .attr("y2", nodeSizeB / 2);

cellB.append("line")
    .attr("class", "arrow")
    .attr("marker-end", "url(#edgeArrowhead)")
    .attr("transform", "translate(" + nodeSizeB / 2 + ", 0)")
    .attr("y1", 0)
    .attr("y2", -nodeMargin * 2 + 5);

cellB.append("text")
    .style("opacity", 0.8)
    .text("B")
    .attr("dx", nodeSi