5.6.1. Source

This field identifies the source package name.

In debian/control or a .dsc file, this field must contain only the name of the source package.

In a binary package control file or a .changes file, the source package name may be followed by a version number in parentheses. 4 This version number may be omitted (and is, by dpkg-gencontrol) if it has the same value as the Version field of the binary package in question. The field itself may be omitted from a binary package control file when the source package has the same name and version as the binary package.

Package names (both source and binary, see Package) must consist only of lower case letters (a-z), digits (0-9), plus (+) and minus (-) signs, and periods (.). They must be at least two characters long and must start with an alphanumeric character.