Simplify model

sok/migrations/0002_auto_20210311_1026.py

@@ -0,0 +1,19 @@
+# Generated by Django 3.1.7 on 2021-03-11 10:26
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('sok', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='publication',
+            name='cite_key',
+            field=models.CharField(default=None, max_length=255, unique=True),
+            preserve_default=False,
+        ),
+    ]

sok/migrations/0003_remove_publication_references_complete.py

@@ -0,0 +1,17 @@
+# Generated by Django 3.1.7 on 2021-03-11 10:27
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('sok', '0002_auto_20210311_1026'),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name='publication',
+            name='references_complete',
+        ),
+    ]