Lambretta saddle seat bolt, washer and spring set for Series 1, 2, 3 with single saddle seats.
The Complete Spanner's Manual: Lambretta Scooters by Martin 'Sticky' Round Third Edition 8100072
The Unofficial Lambretta Manual Update by Mark Haines
LAMBRETTA - ILLUSTRATED GUIDE TO THE IDENTIFICATION by Vittorio Tessera
Lambretta Performance Tuning and Conversions - 8099990