diff --git a/parsedmarc/resources/maps/README.md b/parsedmarc/resources/maps/README.md
index 24845cd..303f813 100644
--- a/parsedmarc/resources/maps/README.md
+++ b/parsedmarc/resources/maps/README.md
@@ -3,6 +3,8 @@
 A mapping is meant to make it easier to identify who or what a sending source is. Please consider contributing
 additional mappings in a GitHub Pull Request.
 
+Do not open these CSV files in Excel. It will replace Unicode characters with question marks. Use LibreOffice Calc instead.
+
 ## base_reverse_dns_map.csv
 
 A CSV file with three fields: `base_reverse_dns`, `name`, and `type`.
@@ -72,7 +74,7 @@ A list of reverse DNS base domains that could not be identified as belonging to
 
 ## base_reverse_dns.csv
 
-A CSV with the fields `source_name` and optionally `message_countcount`. This CSV can be generated byy exporting the base DNS data from the Kibana on Splunk dashboards provided by parsedmarc. This file is not tracked by Git.
+A CSV with the fields `source_name` and optionally `message_count`. This CSV can be generated byy exporting the base DNS data from the Kibana on Splunk dashboards provided by parsedmarc. This file is not tracked by Git.
 
 ## unknown_base_reverse_dns.csv