use warnings;
use strict;

my @records;

$/ = ';';

while (<DATA>) {
    chomp;
    s/\s*(?<!^)\n\s*/ /mg;
    push @records, $_;
}

print join "\n", @records;

__DATA__
The Road Ahead1;Completely Revised and
               Up-to-Date; 002564418
road ahead2; America’a creeping revolution;00345678
The road ahead3;[Address made before the Regional
         Foreign Policy Conference; 004561963
[download]

Prints:

The Road Ahead1
Completely Revised and Up-to-Date
 002564418 road ahead2
 America’a creeping revolution
00345678 The road ahead3
[Address made before the Regional Foreign Policy Conference
 004561963
[download]

which may provide a useful starting point.