diff --git a/dhp-workflows/dhp-aggregation/src/main/java/eu/dnetlib/dhp/collection/plugin/researchfi/ResearchFiIterator.java b/dhp-workflows/dhp-aggregation/src/main/java/eu/dnetlib/dhp/collection/plugin/researchfi/ResearchFiIterator.java
index 269a89f711..cad4999628 100644
--- a/dhp-workflows/dhp-aggregation/src/main/java/eu/dnetlib/dhp/collection/plugin/researchfi/ResearchFiIterator.java
+++ b/dhp-workflows/dhp-aggregation/src/main/java/eu/dnetlib/dhp/collection/plugin/researchfi/ResearchFiIterator.java
@@ -6,7 +6,7 @@ import java.util.Queue;
 import java.util.concurrent.PriorityBlockingQueue;
 
 import org.apache.commons.io.IOUtils;
-import org.apache.commons.lang3.math.NumberUtils;
+import org.apache.commons.lang3.StringUtils;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.http.Header;
@@ -27,25 +27,25 @@ public class ResearchFiIterator implements Iterator<String> {
 
 	private final String baseUrl;
 	private final String authToken;
-	private int currPage;
-	private int nPages;
+	private String nextUrl;
+	private int nCalls = 0;
 
 	private final Queue<String> queue = new PriorityBlockingQueue<>();
 
 	public ResearchFiIterator(final String baseUrl, final String authToken) {
 		this.baseUrl = baseUrl;
 		this.authToken = authToken;
-		this.currPage = 0;
-		this.nPages = 0;
+		this.nextUrl = null;
 	}
 
 	private void verifyStarted() {
-		if (this.currPage == 0) {
-			try {
-				nextCall();
-			} catch (final CollectorException e) {
-				throw new IllegalStateException(e);
+
+		try {
+			if (this.nCalls == 0) {
+				this.nextUrl = invokeUrl(this.baseUrl);
 			}
+		} catch (final CollectorException e) {
+			throw new IllegalStateException(e);
 		}
 	}
 
@@ -62,9 +62,9 @@ public class ResearchFiIterator implements Iterator<String> {
 		synchronized (this.queue) {
 			verifyStarted();
 			final String res = this.queue.poll();
-			while (this.queue.isEmpty() && (this.currPage < this.nPages)) {
+			while (this.queue.isEmpty() && StringUtils.isNotBlank(this.nextUrl)) {
 				try {
-					nextCall();
+					this.nextUrl = invokeUrl(this.nextUrl);
 				} catch (final CollectorException e) {
 					throw new IllegalStateException(e);
 				}
@@ -73,18 +73,11 @@ public class ResearchFiIterator implements Iterator<String> {
 		}
 	}
 
-	private void nextCall() throws CollectorException {
+	private String invokeUrl(final String url) throws CollectorException {
 
-		this.currPage += 1;
+		this.nCalls += 1;
+		String next = null;
 
-		final String url;
-		if (!this.baseUrl.contains("?")) {
-			url = String.format("%s?PageNumber=%d&PageSize=%d", this.baseUrl, this.currPage, PAGE_SIZE);
-		} else if (!this.baseUrl.contains("PageSize=")) {
-			url = String.format("%s&PageNumber=%d&PageSize=%d", this.baseUrl, this.currPage, PAGE_SIZE);
-		} else {
-			url = String.format("%s&PageNumber=%d", this.baseUrl, this.currPage);
-		}
 		log.info("Calling url: " + url);
 
 		try (final CloseableHttpClient client = HttpClients.createDefault()) {
@@ -94,11 +87,15 @@ public class ResearchFiIterator implements Iterator<String> {
 			try (final CloseableHttpResponse response = client.execute(req)) {
 				for (final Header header : response.getAllHeaders()) {
 					log.debug("HEADER: " + header.getName() + " = " + header.getValue());
-					if ("x-page-count".equals(header.getName())) {
-						final int totalPages = NumberUtils.toInt(header.getValue());
-						if (this.nPages != totalPages) {
-							this.nPages = NumberUtils.toInt(header.getValue());
-							log.info("Total pages: " + totalPages);
+					if ("link".equals(header.getName())) {
+						final String s = StringUtils.substringBetween(header.getValue(), "<", ">");
+						final String token = StringUtils
+							.substringBefore(StringUtils.substringAfter(s, "NextPageToken="), "&");
+
+						if (this.baseUrl.contains("?")) {
+							next = this.baseUrl + "&NextPageToken=" + token;
+						} else {
+							next = this.baseUrl + "?NextPageToken=" + token;
 						}
 					}
 				}
@@ -108,6 +105,9 @@ public class ResearchFiIterator implements Iterator<String> {
 
 				jsonArray.forEach(obj -> this.queue.add(JsonUtils.convertToXML(obj.toString())));
 			}
+
+			return next;
+
 		} catch (final Throwable e) {
 			log.warn("Error calling url: " + url, e);
 			throw new CollectorException("Error calling url: " + url, e);