The "Mother" and "Father" bit was a reference to "Effective Medicine for the Worrisome You" /g/539095/e96059d877/ The "flowery panel" joke is also referencing that.
It also came up as a joke in "Classes for Those Bad with Summer!!" /g/669698/f20b674fab/ Alice's sarcastic comment of "Magic can really do anything one wants." is likely also a shout to /s/8580d8eba7/669698-15
The barrier that Alice uses on Shanghai is likely the same one she developed in "We Will Perform a Wonderful Encounter!!" /s/f3bbbd5bc2/503735-32
As for the giant gun... I don't know, maybe Patchouli really liked that one guy from S-cry-ed What I do know is that I enjoy reading Satou Kibi's Alice+Patch too much.