On the subject of style: I like to decompose nested-structure dereferences into "sensical" single-layer dereferences, as below:

#! /usr/bin/perl -w

use strict;

my @AoH=( { chapter => "Basic",        
            page  => [
                { paragraph => "lesson1"},
                { paragraph => "lesson2"}
            ]
           },
           { chapter => "Advanced",
             page  => [
                 { paragraph => "lesson3"},
                 { paragraph => "lesson4"}
             ]
           }
        );

foreach my $ch (@AoH) {
    print $ch->{'chapter'}, "\n";
    my $page = $ch->{'page'};

    foreach my $paras (@$page) {
        print "\t", $paras->{'paragraph'}, "\n";
    }
}
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I find this makes code using these structures easier to read, although longer. It's a judgement call as to whether your structure is dense enough to warrant the extra code.

(I also like to use -> for every deref and single-quote every hash key, but that's a whole different issue....)