A quick and dirty fudge would be :- 
my $data='';

while (<>) {
    my $line=$_;
    $line=~s/[\n\r\l]//g;
    if (length($line)<10) {
        $data.=$line;
    } else {
        if ($data=~m/(?:\s[12]\d{3}\s*\)|\spp.\s+)/) {
        print "$data\n\n";
        $data=$line;
    } else {
            $data.=$line;
        }
    }    
}
print "$data\n\n";

[download]
Looks like that catches the other cases
UnderMine

update: added last print to catch final entry

In reply to Re: Extracting Bibliography Citations by UnderMine
in thread Extracting Bibliography Citations by Limbic~Region

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