Resouces - Calls in resources parallel or sequential

I am taking example provided on Gatling, in below case do api.js and ga.js get executed in parallel or in sequence?

http(“Getting issues”)
.get(“https://www.github.com/gatling/gatling/issues”)
.resources(
http(“api.js”).get(“https://collector-cdn.github.com/assets/api.js”),
http(“ga.js”).get(“https://ssl.google-analytics.com/ga.js”)
)