adding acknowledgement

database_functions.sh

@@ -6,6 +6,7 @@
 # @purpose: Runs database functions for the Experimental Publishing Compendium
 # @acknowledgements:
 # https://www.redhat.com/sysadmin/arguments-options-bash-scripts
+# https://askubuntu.com/questions/1389904/read-from-env-file-and-set-as-bash-variables
 
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 # subprograms                                              #