Stopping supplies of raw materials ('one of the most important methods of compelling adherence to the cartel'); Stopping the supply of labor by means of 'alliances' (i.e., of agreements between employers and the trade unions by which the latter permit their members to work only in trustified enterprises); Cutting off deliveries; Closing of trade outlets; Agreements with the buyers, by which the latter undertake to trade only with the cartels; The systematic lowering of prices to ruin 'outside' firms,.e., those who refuse to submit to the trust.