added fulltext field on the instance level

src/main/java/eu/dnetlib/dhp/schema/oaf/Instance.java

@@ -39,6 +39,11 @@ public class Instance implements Serializable {
 
 	private List<Measure> measures;
 
+	/**
+	 * Direct fulltext URL.
+	 */
+	private String fulltext;
+
 	public Field<String> getLicense() {
 		return license;
 	}
@@ -151,6 +156,14 @@ public class Instance implements Serializable {
 		this.measures = measures;
 	}
 
+	public String getFulltext() {
+		return fulltext;
+	}
+
+	public void setFulltext(String fulltext) {
+		this.fulltext = fulltext;
+	}
+
 	public String toComparableString() {
 		return String
 			.format(

src/main/java/eu/dnetlib/dhp/schema/oaf/Result.java

@@ -95,9 +95,9 @@ public class Result extends OafEntity implements Serializable {
 	private List<Field<String>> source;
 
 	/**
-	 * The Fulltext.
+	 * The list of direct fulltext URLs.
 	 */
-	private List<Field<String>> fulltext; // remove candidate
+	private List<Field<String>> fulltext;
 
 	/**
 	 * The Format.