diff --git a/Gemfile b/Gemfile
index 1c12d8d..c8e28d0 100644
--- a/Gemfile
+++ b/Gemfile
@@ -5,7 +5,7 @@ gem "dotenv"
 gem "oj", ">= 3.1.0"
 gem "oj_mimic_json", "~> 1.0", ">= 1.0.1"
 gem "equivalent-xml", "~> 0.6.0"
-gem "nokogiri", ">= 1.10.4"
+gem "nokogiri", ">= 1.10.8"
 gem "iso8601", "~> 0.9.0"
 gem "maremma", ">= 4.1"
 gem "faraday", "0.17.0"
@@ -19,7 +19,6 @@ gem "gender_detector", "~> 0.1.2"
 gem "rack-cors", "~> 1.0", require: "rack/cors"
 gem "git", "~> 1.5"
 gem "sprockets", "~> 3.7", ">= 3.7.2"
-gem 'json-ld-preloaded', '~> 3.0', '>= 3.0.2'
 
 group :development do
   gem "better_errors"
@@ -35,7 +34,7 @@ end
 group :test do
   gem "rspec-rails", "~> 3.5", ">= 3.5.2"
   gem "capybara"
-  gem "webmock", "~> 1.20.0"
+  gem "webmock", "~> 3.8", ">= 3.8.2"
   gem "vcr", "~> 3.0.3"
   gem 'simplecov', '~> 0.17.1'
 end
diff --git a/Gemfile.lock b/Gemfile.lock
index 2037664..710e014 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -51,24 +51,24 @@ GEM
       coderay (>= 1.0.0)
       erubi (>= 1.0.0)
       rack (>= 0.9.0)
-    bibtex-ruby (4.4.7)
+    bibtex-ruby (5.1.1)
       latex-decode (~> 0.0)
     binding_of_caller (0.8.0)
       debug_inspector (>= 0.0.1)
-    bolognese (1.4.3)
-      activesupport (>= 4.2.5, < 6)
+    bolognese (1.5.14)
+      activesupport (>= 4.2.5)
       benchmark_methods (~> 0.7)
-      bibtex-ruby (~> 4.1)
+      bibtex-ruby (>= 5.1.0)
       builder (~> 3.2, >= 3.2.2)
       citeproc-ruby (~> 1.1, >= 1.1.10)
       colorize (~> 0.8.1)
-      concurrent-ruby (~> 1.0.5)
+      concurrent-ruby (~> 1.1, >= 1.1.5)
       csl-styles (~> 1.0, >= 1.0.1.8)
       edtf (~> 3.0, >= 3.0.4)
       faraday (= 0.17.0)
       gender_detector (~> 0.1.2)
       iso8601 (~> 0.9.1)
-      json-ld-preloaded (~> 3.0)
+      json-ld (~> 2.2, >= 2.2.1)
       jsonlint (~> 0.3.0)
       loofah (~> 2.0, >= 2.0.3)
       maremma (>= 4.3, < 5)
@@ -77,8 +77,8 @@ GEM
       oj (~> 3.10)
       oj_mimic_json (~> 1.0, >= 1.0.1)
       postrank-uri (~> 1.0, >= 1.0.18)
-      rdf-rdfxml (~> 2.2)
-      rdf-turtle (~> 3.0, >= 3.0.6)
+      rdf-rdfxml (~> 3.1)
+      rdf-turtle (~> 3.1)
       thor (~> 0.19)
     builder (3.2.4)
     capybara (3.31.0)
@@ -96,7 +96,7 @@ GEM
       csl (~> 1.5)
     coderay (1.1.2)
     colorize (0.8.1)
-    concurrent-ruby (1.0.5)
+    concurrent-ruby (1.1.6)
     crack (0.4.3)
       safe_yaml (~> 1.0.0)
     crass (1.0.6)
@@ -136,23 +136,16 @@ GEM
       tilt
     hamster (3.0.0)
       concurrent-ruby (~> 1.0)
+    hashdiff (1.0.0)
     htmlentities (4.3.4)
     i18n (1.8.2)
       concurrent-ruby (~> 1.0)
     iso8601 (0.9.1)
     jaro_winkler (1.5.4)
     json (2.3.0)
-    json-canonicalization (0.2.0)
-    json-ld (3.1.0)
-      htmlentities (~> 4.3)
-      json-canonicalization (~> 0.1)
-      link_header (~> 0.0, >= 0.0.8)
-      multi_json (~> 1.14)
-      rack (~> 2.0)
-      rdf (~> 3.1)
-    json-ld-preloaded (3.1.0)
-      json-ld (~> 3.1)
-      rdf (~> 3.1)
+    json-ld (2.2.1)
+      multi_json (~> 1.12)
+      rdf (>= 2.2.8, < 4.0)
     jsonlint (0.3.0)
       oj (~> 3)
       optimist (~> 3)
@@ -176,8 +169,8 @@ GEM
       mini_mime (>= 0.1.1)
     marcel (0.3.3)
       mimemagic (~> 0.3.2)
-    maremma (4.5)
-      activesupport (>= 4.2.5, < 6)
+    maremma (4.6)
+      activesupport (>= 4.2.5)
       addressable (>= 2.3.6)
       builder (~> 3.2, >= 3.2.2)
       excon (~> 0.71.0)
@@ -196,7 +189,7 @@ GEM
     multipart-post (2.1.1)
     namae (1.0.1)
     nio4r (2.5.2)
-    nokogiri (1.10.7)
+    nokogiri (1.10.8)
       mini_portile2 (~> 2.4.0)
     oj (3.10.2)
     oj_mimic_json (1.0.1)
@@ -209,7 +202,7 @@ GEM
       nokogiri (>= 1.8.0)
       public_suffix (>= 2.0.0, < 2.1)
     public_suffix (2.0.5)
-    rack (2.1.2)
+    rack (2.2.2)
     rack-cors (1.1.1)
       rack (>= 2.0.0)
     rack-test (1.1.0)
@@ -255,17 +248,17 @@ GEM
       rdf (~> 3.1)
       rdf-aggregate-repo (~> 3.1)
       rdf-xsd (~> 3.1)
-    rdf-rdfxml (2.2.1)
+    rdf-rdfxml (3.1.0)
       htmlentities (~> 4.3)
-      rdf (>= 2.2, < 4.0)
-      rdf-rdfa (>= 2.2, < 4.0)
-      rdf-xsd (>= 2.2, < 4.0)
+      rdf (~> 3.1)
+      rdf-rdfa (~> 3.1)
+      rdf-xsd (~> 3.1)
     rdf-turtle (3.1.0)
       ebnf (~> 1.2)
       rdf (~> 3.1)
     rdf-xsd (3.1.0)
       rdf (~> 3.1)
-    regexp_parser (1.6.0)
+    regexp_parser (1.7.0)
     request_store (1.5.0)
       rack (>= 1.4)
     rspec-core (3.9.1)
@@ -328,9 +321,10 @@ GEM
     unicode-display_width (1.6.1)
     unicode_utils (1.4.0)
     vcr (3.0.3)
-    webmock (1.20.4)
+    webmock (3.8.2)
       addressable (>= 2.3.6)
       crack (>= 0.3.2)
+      hashdiff (>= 0.4.0, < 2.0.0)
     websocket-driver (0.7.1)
       websocket-extensions (>= 0.1.0)
     websocket-extensions (0.1.4)
@@ -352,13 +346,12 @@ DEPENDENCIES
   gender_detector (~> 0.1.2)
   git (~> 1.5)
   iso8601 (~> 0.9.0)
-  json-ld-preloaded (~> 3.0, >= 3.0.2)
   listen (~> 3.0.5)
   lograge (~> 0.11.2)
   logstash-event (~> 1.2, >= 1.2.02)
   logstash-logger (~> 0.26.1)
   maremma (>= 4.1)
-  nokogiri (>= 1.10.4)
+  nokogiri (>= 1.10.8)
   oj (>= 3.1.0)
   oj_mimic_json (~> 1.0, >= 1.0.1)
   rack-cors (~> 1.0)
@@ -373,7 +366,7 @@ DEPENDENCIES
   spring-watcher-listen (~> 2.0.0)
   sprockets (~> 3.7, >= 3.7.2)
   vcr (~> 3.0.3)
-  webmock (~> 1.20.0)
+  webmock (~> 3.8, >= 3.8.2)
 
 BUNDLED WITH
    2.1.4