[aldoxime_amine]

This is a question from M and B from aldehydes and ketones chapter.

2 mechanisms can be suggested for the following reaction depending on our way of interpreting it.

One proceeding by nucleophilic adiition and other by electrophilic addition.
I could identify the 2nd part (electrophilic attack by acyl carbon on the double bond at 2nd positon).
However, i coud not identify the first. Help would be appreciated.

[vhpk]

I suppose this's an electrophilic addition due to the electrophilic agent, proton. So the bond where it has the rich density of electron will be the centre of reaction.