cleanup some citations

Author: hacdias

mature/src/http-gateways/path-gateway.md

@@ -17,11 +17,9 @@ provides basic primitives for integrating IPFS resources within existing HTTP
 stack.
 
 **Note:** additional Web Gateways aimed for website hosting and web browsers
-extend the below spec and are defined in
-[SUBDOMAIN_GATEWAY.md](./SUBDOMAIN_GATEWAY.md) and
-[DNSLINK_GATEWAY.md](./DNSLINK_GATEWAY.md). There is also a minimal
-[TRUSTLESS_GATEWAY.md](./TRUSTLESS_GATEWAY.md) specification for use cases
-where client prefers to perform all validation locally.
+extend the below spec and are defined in :cite[subdomain-gateway] and
+:cite[dnslink-gateway]. There is also a minimal :cite[trustless-gateway]
+specification for use cases where client prefers to perform all validation locally.
 
 # HTTP API
 

mature/src/http-gateways/subdomain-gateway.md

@@ -158,7 +158,7 @@ See: [URI router](#uri-router)
 
 ## Migrating from Path to Subdomain Gateway
 
-Subdomain Gateway MUST implement a redirect on paths defined in [`PATH_GATEWAY.md`](./PATH_GATEWAY.md).
+Subdomain Gateway MUST implement a redirect on paths defined in :cite[path-gateway].
 
 HTTP redirect will route path requests to correct subdomains on the same domain
 name, unless [`X-Forwarded-Host`](#x-forwarded-host-request-header) is present.