* [http://www.nakka-rocketry.net/paracon.html Parachute Design and Construction] by Richard Nakka
* [http://www.nakka-rocketry.net/paracon.html Parachute Design and Construction] by Richard Nakka
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* [https://gallery.mailchimp.com/c4ab65df2b61279e33d7ee72b/files/HAB_Parachute_Size_Estimator_v1.0.xlsx Parachute Size Estimator tool] using imperial unit system ([https://www.launchwithus.org/lwu-blog/2016/02/17/parachute-size-estimator-for-high-altitude-balloons Launchwithus.org])