Regular meetings of members shall be held as prescribed in the by-laws [bylaws], but shall be held at least once a year. Special meetings may be demanded by a majority vote of the directors or by written petition of at least one-tenth of the members, in which case it shall be the duty of the secretary to call such meeting to take place within 30 days after such demand. Regular or special meetings, including meetings by units as hereinafter provided, may be held within or without this state as the articles or by-laws [bylaws] may prescribe.