diff --git a/CHANGELOG.md b/CHANGELOG.md
index ec66e03d..f8d551ba 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,8 @@
 
 ## Unreleased
 
+- Accept loading OAD documents with numeric status codes. Fixes "Unknown reference" error. https://github.com/ahx/openapi_first/issues/367
+
 - Support QUERY request method
   OpenAPI 3.0, 3.1 does not support that, but this does
 
diff --git a/lib/openapi_first.rb b/lib/openapi_first.rb
index 07fb5405..3989cc1d 100644
--- a/lib/openapi_first.rb
+++ b/lib/openapi_first.rb
@@ -64,8 +64,9 @@ def self.load(filepath_or_definition, only: nil, &)
 
   # Parse a dereferenced Hash
   # @return [Definition]
+  # TODO: This needs to work with unresolved contents as well
   def self.parse(contents, only: nil, filepath: nil, &)
-    # TODO: This needs to work with unresolved contents as well
+    contents = JSON.parse(JSON.generate(contents)) # Deeply stringify keys, because of YAML. See https://github.com/ahx/openapi_first/issues/367
     contents['paths'].filter!(&->(key, _) { only.call(key) }) if only
     Definition.new(contents, filepath, &)
   end
diff --git a/lib/openapi_first/file_loader.rb b/lib/openapi_first/file_loader.rb
index 531035c2..ab93e2f6 100644
--- a/lib/openapi_first/file_loader.rb
+++ b/lib/openapi_first/file_loader.rb
@@ -1,5 +1,6 @@
 # frozen_string_literal: true
 
+require 'json'
 require 'yaml'
 
 module OpenapiFirst
diff --git a/spec/data/numeric-status.yaml b/spec/data/numeric-status.yaml
new file mode 100644
index 00000000..a9d5f1f5
--- /dev/null
+++ b/spec/data/numeric-status.yaml
@@ -0,0 +1,27 @@
+openapi: 3.0.2
+info:
+  title: Acme Control API
+  version: 0.0.1
+paths:
+  /roles:
+    get:
+      responses:
+        200:
+          content:
+            application/json:
+              schema:
+                type: object
+  /roles/query:
+    post:
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+                type: object
+      responses:
+        200:
+          content:
+            application/json:
+              schema:
+                $ref: '#/paths/~1roles/get/responses/200/content/application~1json/schema'
diff --git a/spec/openapi_first_spec.rb b/spec/openapi_first_spec.rb
index 92feca36..d0ba9b21 100644
--- a/spec/openapi_first_spec.rb
+++ b/spec/openapi_first_spec.rb
@@ -47,6 +47,11 @@
       expect(definition.paths).to include('/foo')
     end
 
+    it 'works with numeric statuses' do
+      definition = OpenapiFirst.load('./spec/data/numeric-status.yaml')
+      expect(definition.paths).to include('/roles')
+    end
+
     it 'works with YAML' do
       definition = OpenapiFirst.load('./spec/data/petstore.yaml')
       expect(definition.paths).to include('/pets')