$ for i in $(apt-cache depends lightdm  | grep Depends | awk '{ print $2 }'); do dpkg -l | grep  $i; done 
ii  debconf                                1.5.42ubuntu1                                  Debian configuration management system
ii  debconf-i18n                           1.5.42ubuntu1                                  full internationalization support for debconf
ii  po-debconf                             1.0.16+nmu2ubuntu1                             tool for managing templates file translations with gettext
ii  ssl-cert                               1.0.28                                         simple debconf wrapper for OpenSSL
ii  libc6                                  2.15-0ubuntu6                                  Embedded GNU C Library: Shared libraries
ii  libc6-dev                              2.15-0ubuntu6                                  Embedded GNU C Library: Development Libraries and Header Files
ii  libglib2.0-0                           2.31.22-0ubuntu1                               GLib library of C routines
ii  libpam0g                               1.1.3-7ubuntu2                                 Pluggable Authentication Modules library
ii  libxcb1                                1.8.1-1                                        X C Binding
ii  libxcb1-dev                            1.8.1-1                                        X C Binding, development files
ii  libxdmcp6                              1:1.1.0-4                                      X11 Display Manager Control Protocol library
ii  libpam-runtime                         1.1.3-7ubuntu2                                 Runtime support for the PAM library
ii  libpam-modules                         1.1.3-7ubuntu2                                 Pluggable Authentication Modules for PAM
ii  libpam-modules-bin                     1.1.3-7ubuntu2                                 Pluggable Authentication Modules for PAM - helper binaries
ii  adduser                                3.113ubuntu2                                   add and remove users and groups
ii  libglib2.0-bin                         2.31.22-0ubuntu1                               Programs for the GLib library
ii  at-spi2-core                           2.3.92-1                                       Assistive Technology Service Provider Interface (dbus core)
ii  dbus                                   1.4.18-1ubuntu1                                simple interprocess messaging system (daemon and utilities)
ii  dbus-x11                               1.4.18-1ubuntu1                                simple interprocess messaging system (X11 deps)
ii  gir1.2-dbusmenu-glib-0.4               0.5.95-0ubuntu1                                typelib file for libdbusmenu-glib4
ii  gir1.2-dbusmenu-gtk-0.4                0.5.95-0ubuntu1                                typelib file for libdbusmenu-gtk4
ii  libaudclient2                          3.2.1-2                                        audacious dbus remote control library
ii  libdbus-1-3                            1.4.18-1ubuntu1                                simple interprocess messaging system (library)
ii  libdbus-glib-1-2                       0.98-1ubuntu1                                  simple interprocess messaging system (GLib-based shared library)
ii  libdbusmenu-glib4                      0.5.95-0ubuntu1                                library for passing menus over DBus
ii  libdbusmenu-gtk3-4                     0.5.95-0ubuntu1                                library for passing menus over DBus - GTK+ version
ii  libdbusmenu-gtk4                       0.5.95-0ubuntu1                                library for passing menus over DBus - GTK+ version
ii  libdbusmenu-qt2                        0.9.0-2ubuntu1                                 Qt implementation of the DBusMenu protocol
ii  libnet-dbus-perl                       1.0.0-1build1                                  Extension for the DBus bindings
ii  libnih-dbus1                           1.0.3-4ubuntu9                                 NIH D-Bus Bindings Library
ii  libqt4-dbus                            4:4.8.0-1ubuntu11                              Qt 4 D-Bus module
ii  python-dbus                            1.0.0-1ubuntu1                                 simple interprocess messaging system (Python interface)
ii  python-dbus-dev                        1.0.0-1ubuntu1                                 main loop integration development files for python-dbus
ii  python-qt4-dbus                        4.9.1-2                                        DBus Support for PyQt4
ii  qdbus                                  4:4.8.0-1ubuntu11                              Qt 4 D-Bus tool
ii  dpkg                                   1.16.1.2ubuntu5                                Debian package management system
ii  dpkg-dev                               1.16.1.2ubuntu5                                Debian package development tools
ii  libdpkg-perl                           1.16.1.2ubuntu5                                Dpkg perl modules