Create points on a D3 multiline graph

Question

I\'m trying to add points to a line graph using d3 in this example: http://bl.ocks.org/mbostock/3884955

I was also trying to follow this post

How do you get

Answer 1

.style("stroke", function(d) { return color(this.parentNode.__data__.name); })

See JSBin code
Found answer here