diff --git a/rdf/tool/amalgame.ttl b/rdf/tool/amalgame.ttl
index 2bd5869..9511a84 100644
--- a/rdf/tool/amalgame.ttl
+++ b/rdf/tool/amalgame.ttl
@@ -70,25 +70,31 @@ amalgame:Merger
     rdfs:subClassOf amalgame:Process .
 
 amalgame:includes
+	a rdf:Property ;
         rdfs:domain skos:ConceptScheme ;
         rdfs:range amalgame:AlignmentStrategy .
 amalgame:input
+	a rdf:Property ;
 	rdfs:domain amalgame:Process ;
 	rdfs:range amalgame:Entity ;
 	rdfs:subPropertyOf prov:used.
 amalgame:secondary_input
+	a rdf:Property ;
 	rdfs:domain amalgame:Process ;
 	rdfs:range amalgame:Entity ;
 	rdfs:subPropertyOf prov:used .
 amalgame:need_secondary_inputs
+	a rdf:Property ;
 	rdfs:domain amalgame:Process ;
 	rdfs:range xsd:boolean ;
+	rdfs:comment 'True for processes that need more than the standard primary inputs associated to their type.'@en.
 amalgame:wasGeneratedBy 
 	a rdf:Property ;
 	rdfs:domain amalgame:Entity ;
 	rdfs:range amalgame:Process ;
 	rdfs:comment 'The subject can be generated by running the object'@en.
 amalgame:selectedBy
+	a rdf:Property ;
 	rdfs:domain amalgame:Entity ;
 	rdfs:range amalgame:Process ;
 	rdfs:subPropertyOf amalgame:wasGeneratedBy.