diff --git a/Dockerfile b/Dockerfile
index adeb335..7201e88 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM python
+FROM python:alpine
 
 WORKDIR /srv
 
diff --git a/README.md b/README.md
index d289994..1827be1 100644
--- a/README.md
+++ b/README.md
@@ -42,7 +42,7 @@ Simple docker deployment
 docker build . -t publite_backend
 
 # run it with docker
-docker run -p <port>:80 publite_backend
+docker run -p <port>:8081 publite_backend
 ```
 
 Dokku deployment with image from Docker Hub
diff --git a/app/fb2.py b/app/fb2.py
index 7300d8a..66ffecb 100644
--- a/app/fb2.py
+++ b/app/fb2.py
@@ -115,7 +115,7 @@ def get_author(author: Element) -> str:
         "last-name",
     ):
         tag = author.find("./" + tag_name, namespaces)
-        if tag is not None:
+        if tag is not None and tag.text is not None:
             res.append(tag.text)
     if len(res) == 0:
         res = author.find("./nickname", namespaces).text
diff --git a/app/utils.py b/app/utils.py
index f14c18a..4099e77 100644
--- a/app/utils.py
+++ b/app/utils.py
@@ -17,7 +17,7 @@ class HTMLBook(BaseModel):  # pylint: disable=too-few-public-methods
 
     title: str
     author: str
-    cover: Optional[str]
+    cover: Optional[str] = None
     content: str