B4 La Cité Perdue

First print (1983).  Printed by TSR.  Purple cover.  Matches the US Third print, with the exception that roughly one-third of the interior artwork is missing, and much of the remaining artwork has been re-sized and shuffled around.  Thanks to Michael Deaton for this info, and the scan.

Second print (1986).  Printed by Transecom.  Blue cover.  Released soon after the Third French print of the D&D Basic Set in 1985.  Aside from the wording on the upper half of the cover, and the cover color, unknown how this print compares with the First print above.  Thanks to Slaheddine Kefi for the scan.

B4 Die Vergessene Stadt

Thanks to Olav Riediger for the scan.

B4 La Citta Perduta

First print:  Interior is identical to the US version.  Rear cover states "Printed in Spain".  This print appears to be rarer than the Second print below.  Thanks to Ciro Alessandro Sacco for this info, and to Ciro Alessandro Sacco and Danilo Moretti for the scan.

Second print:  Interior is identical to the US version.  Rear cover states "Printed in Italy".  Thanks to Ciro Alessandro Sacco for this info, and to Ciro Alessandro Sacco and Danilo Moretti for the scan.

B4 Lost City

First print:  Lacks the "swoosh" graphic.  Thanks to Adrian Newman for this info, and the scan.

Second print:  Thanks to Richard van Tol for the scan.

B4 La Ciudad Perdida

Aside from translation, identical to US version.  Unknown which US print this matches, however.  Thanks to Andrés Otero for this info and to Abel Ferrer for the scan.

B4 Den glömda staden

Size is UK-standard A4.  No other differences.  Thanks to Niklas Nordgren for the scan.