Add API reference links to parameters.md

Author: gerwyn-ng

docs/parameters.md

@@ -3,28 +3,28 @@
 
 Request parameters constrain the data an endpoint returns. **All request parameter values must be [URL-encoded](https://en.wikipedia.org/wiki/Percent-encoding)**.
 
-The following parameters expect values in a special syntax. For each endpoint's full list of required and optional parameters, visit the API reference.
+The following parameters expect values in a special syntax. For each endpoint's full list of required and optional parameters, visit the [API reference](api-reference.md).
 
 ## `select`
 
 Example: `field_a,field_b,field_c`
 
 A mandatory comma-separated list of field names. This specifies which fields to return from the endpoint. Not all endpoints accept this parameter.
 
-See the endpoint's response schema in the API reference for the list of valid field names.
+See the endpoint's response schema in the [API reference](api-reference.md) for the list of valid field names.
 
 ## `where`
 
 Example: `{"and":[{"field":"field_a","is":["gt",90]},{"field":"field_b","is":["eq","SEO"]}]}`
 
 A *filter expression* to narrow down the results. The syntax is described in detail in [Filter syntax](./filter-syntax.md). Not all endpoints accept this parameter.
 
-See the endpoint's parameter description in the API reference for the list of valid field names that can be used in the filter expression. **This may differ from the `select` parameter's field name list.**
+See the endpoint's parameter description in the [API reference](api-reference.md) for the list of valid field names that can be used in the filter expression. **This may differ from the `select` parameter's field name list.**
 
 ## `order_by`
 
 Example: `field_a:desc,field_b:asc`
 
 Orders the results by the specified field(s) and direction (`desc` or `asc`). Not all endpoints accept this parameter.
 
-See the endpoint's response schema in the API reference for the list of valid field names. This is the same as the `select` parameter's field name list.
+See the endpoint's response schema in the [API reference](api-reference.md) for the list of valid field names. This is the same as the `select` parameter's field name list.