Modify reference with doi plugin (really this time)

content/2.defense-systems/abia.md

content/2.defense-systems/abib.md

content/2.defense-systems/abic.md

content/2.defense-systems/abid.md

content/2.defense-systems/abie.md

content/2.defense-systems/abig.md

content/2.defense-systems/abih.md

content/2.defense-systems/abii.md

content/2.defense-systems/abij.md

content/2.defense-systems/abik.md

content/2.defense-systems/abil.md

content/2.defense-systems/abin.md

content/2.defense-systems/abio.md

content/2.defense-systems/abip2.md

content/2.defense-systems/abiq.md

content/2.defense-systems/abir.md

content/2.defense-systems/abit.md

content/2.defense-systems/abiu.md

content/2.defense-systems/abiv.md

content/2.defense-systems/abiz.md