diff --git a/dhp-workflows/dhp-doiboost/src/test/java/eu/dnetlib/dhp/doiboost/NormalizeDoiTest.scala b/dhp-workflows/dhp-doiboost/src/test/java/eu/dnetlib/dhp/doiboost/NormalizeDoiTest.scala
new file mode 100644
index 000000000..a9a841ee9
--- /dev/null
+++ b/dhp-workflows/dhp-doiboost/src/test/java/eu/dnetlib/dhp/doiboost/NormalizeDoiTest.scala
@@ -0,0 +1,46 @@
+package eu.dnetlib.dhp.doiboost
+
+import eu.dnetlib.doiboost.DoiBoostMappingUtil
+import org.junit.jupiter.api.Test
+
+class NormalizeDOITest {
+
+  @Test
+  def doiDSLowerCase():Unit = {
+    val doi ="10.1042/BCJ20160876"
+
+    assert(DoiBoostMappingUtil.normalizeDoi(doi).equals(doi.toLowerCase()))
+
+  }
+
+
+  @Test
+  def doiFiltered():Unit = {
+    val doi = "0.1042/BCJ20160876"
+
+    assert(DoiBoostMappingUtil.normalizeDoi(doi) == null)
+  }
+
+  @Test
+  def doiFiltered2():Unit = {
+    val doi = "https://doi.org/0.1042/BCJ20160876"
+
+    assert(DoiBoostMappingUtil.normalizeDoi(doi) == null)
+  }
+
+
+  @Test
+  def doiCleaned():Unit = {
+    val doi = "https://doi.org/10.1042/BCJ20160876"
+
+    assert(DoiBoostMappingUtil.normalizeDoi(doi).equals("10.1042/BCJ20160876".toLowerCase()))
+  }
+
+  @Test
+  def doiCleaned1():Unit = {
+    val doi = "https://doi.org/10.1042/ BCJ20160876"
+
+    assert(DoiBoostMappingUtil.normalizeDoi(doi).equals("10.1042/BCJ20160876".toLowerCase()))
+  }
+
+}
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