<?php
$date = mktime(0, 0, 0, 1, 1, 2000);
// MMMM is the month name when used in date strings
$mmmm = new IntlDateFormatter("ru_RU.UTF-8", IntlDateFormatter::FULL, IntlDateFormatter::FULL, null, null, "MMMM");
echo "MMMM = ", $mmmm->format($date), "\n";
// LLLL is the "stand alone" month name when used by itself
$llll = new IntlDateFormatter("ru_RU.UTF-8", IntlDateFormatter::FULL, IntlDateFormatter::FULL, null, null, "LLLL");
echo "LLLL = ", $llll->format($date);
// use mb_convert_case to uppercase the first letter
echo " or ", mb_convert_case($llll->format($date), MB_CASE_TITLE);