A world volume action for membrane is considered to study the target s
pace local symmetries. We introduce a set of generators of canonical t
ransformations to exhibit the target space symmetries such as the gene
ral coordinate transformation and the gauge transformation of antisymm
etric tensor field. Similar results are derived for type IIB string wi
th manifestly S-duality-invariant worldsheet action. (C) 1998 Elsevier
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