00803nam0-22002891i-450-9900010270404033210-12-454750-8000102704FED01000102704(Aleph)000102704FED0100010270420000920d1977----km-y0itay50------baengInvariant variational principlesDavid John LoganNew YorkAcademic Press1977Mathematics in science and engineering138Meccanica classica531Logan,John David48876ITUNINARICAUNIMARCBK99000102704040332124-08710844FI1FI1Invariant variational principles339402UNINAING01