diff --git a/openapi/ver/current/skg-if-openapi.yaml b/openapi/ver/current/skg-if-openapi.yaml
index dbf3ef7..fab69a9 100644
--- a/openapi/ver/current/skg-if-openapi.yaml
+++ b/openapi/ver/current/skg-if-openapi.yaml
@@ -46,7 +46,23 @@ tags: # upper case name
     description: Pagination description (can use markdown syntax)
     x-traitTag: true
 servers:
-  - url: 'http://example.com/skg-if/api'
+  - url: '{protocol}://{server}:{port}/{skg_if_api_path}'
+    variables:
+      protocol:
+        enum:
+          - "https"
+          - "http"
+        default: "https"
+        description: service provider protocol.
+      server:
+        default: example.com
+        description: service provider server.
+      port:
+        default: "8443"
+        description: service provider port.
+      skg_if_api_path:
+        default: skg-if/api
+        description: service provider skg-if api path
 paths:
   '/products/{short_local_identifier}':
     get:
@@ -224,10 +240,10 @@ paths:
           | cf.contributions_orcid | a string | `product` with contributor with orcid value | `cf.contributions_orcid:0000-0002-1825-0097` |
           | cf.contributions_aff_ror | a string | `product` with contributor with declared_affiliations ror value | `cf.contributions_aff_ror:05gq02987` |
           | cf.contributions_aff_country | a string | `product` with contributor with declared_affiliations country value | `cf.contributions_aff_country:us` |
-          | cf.cites | a local_identifier | `product` that cites the `product` having local_identifier filter value | `cf.cites:prod_1` |
-          | cf.cited_by | a local_identifier | `product` that cites the `product` having local_identifier filter value | `cf.cited_by:prod_1` |
-          | cf.cites_doi | a doi | `product` that cites the `product` having doi filter value | `cf.cites_doi:10.1038/sdata.2016.18` |
-          | cf.cited_by_doi | a doi | `product` that cites the `product` having doi filter value | `cf.cited_by_doi:10.1038/sdata.2016.18` |
+          | cf.cites | a local_identifier | `product` citing the `product` having local_identifier filter value | `cf.cites:prod_1` |
+          | cf.cited_by | a local_identifier | `product` cited by the `product` having local_identifier filter value | `cf.cited_by:prod_1` |
+          | cf.cites_doi | a doi | `product` citing the `product` having doi filter value | `cf.cites_doi:10.1038/sdata.2016.18` |
+          | cf.cited_by_doi | a doi | `product` cited by the `product` having doi filter value | `cf.cited_by_doi:10.1038/sdata.2016.18` |
 
 
           __Query parameter syntax examples__ \