diff --git a/src/main/java/cat/udl/eps/softarch/demo/domain/ShelterCertificate.java b/src/main/java/cat/udl/eps/softarch/demo/domain/ShelterCertificate.java
index f95d17af..51d6a760 100644
--- a/src/main/java/cat/udl/eps/softarch/demo/domain/ShelterCertificate.java
+++ b/src/main/java/cat/udl/eps/softarch/demo/domain/ShelterCertificate.java
@@ -1,14 +1,30 @@
 package cat.udl.eps.softarch.demo.domain;
 
-import java.util.Date;
+import java.time.ZonedDateTime;
+import com.fasterxml.jackson.annotation.JsonIdentityReference;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import jakarta.persistence.ManyToOne;
+import jakarta.validation.constraints.NotNull;
+import lombok.Data;
+import lombok.EqualsAndHashCode;
 
+@EqualsAndHashCode(callSuper = true)
+@Data
+@Entity
 public class ShelterCertificate extends UriEntity<Long> {
-    
+
+    @Id
+    @GeneratedValue()
     private Long id;
-    private Date expirationDate;
 
-    @Override
-    public Long getId() {
-        return id;
-    }
+    @JsonProperty(access = JsonProperty.Access.READ_ONLY)
+    @NotNull
+    private ZonedDateTime expirationDate;
+
+    @JsonIdentityReference(alwaysAsId = true)
+    @ManyToOne
+    private Shelter shelterServed;
 }
diff --git a/src/main/java/cat/udl/eps/softarch/demo/repository/ShelterCertificateRepository.java b/src/main/java/cat/udl/eps/softarch/demo/repository/ShelterCertificateRepository.java
new file mode 100644
index 00000000..114d4322
--- /dev/null
+++ b/src/main/java/cat/udl/eps/softarch/demo/repository/ShelterCertificateRepository.java
@@ -0,0 +1,9 @@
+package cat.udl.eps.softarch.demo.repository;
+
+import cat.udl.eps.softarch.demo.domain.ShelterCertificate;
+import org.springframework.data.repository.CrudRepository;
+import org.springframework.data.repository.PagingAndSortingRepository;
+
+public interface ShelterCertificateRepository extends CrudRepository<ShelterCertificate, Long>, PagingAndSortingRepository<ShelterCertificate, Long> {
+
+}