Mayor Yury Luzhkov has ordered sharp limitations on the sale of erotic publications to take effect in September, a city official said Friday. In addition, foreign erotic publications will be required to obtain official permission to circulate, Vladimir Petukhov, an official in the mayor's office, said.He said Luzhkov's order, issued last month, banned the sale of erotic publications in railroad and metro stations, airports, and in the street. The measure was aimed at encouraging "the positive upbringing of younger generation," Petukhov said."We are not going to ban publication and sale of erotic materials," he said. Yet he added that it is time to limit their availability. "Look what is going on. Even small children can easily buy any erotic newspaper, practically anywhere."The order envisages the creation of special shops and kiosks for the sale of erotic publications. It also bans the sale of erotic publications to children under 16 years old. Petukhov pointed out that there could be difficulties and abuses in implementing the order because it does not create a definition of what is erotic, nor does it distinguish between erotic and pornographic publications. Mikhail Zherlitsyn, deputy editor of the erotic newspaper Krasnaya Shapochka, called the order "legally ignorant".  Alexei Kostin, the publisher of the sexually explicit newspaper Yeshcho, was imprisoned in February on charges of distributing pornography, although the weekly newspaper is officially registered and has not been banned.