_W_r_i_t_e _t_e_x_t _i_n_t_o _t_h_e _m_a_r_g_i_n_s _o_f _a _p_l_o_t
	
	     mtext(text=, side=3, line=0, outer=FALSE, at=, ...)
	
	_A_r_g_u_m_e_n_t_s:
	
	        text : character string to be written
	
	        side : on which side of the plot (1=bottom, 2=left,
	               3=top, 4=right)
	
	        line : on which MARgin line, starting at 0 counting
	               outwards
	
	       outer : use outer margins if available
	
	          at : give location in user-coordinates
	
	_D_e_s_c_r_i_p_t_i_o_n:
	
	     text is written in one of the four margins (side) of
	     the plot.  line measures the distance outwardly in
	     character size units.
	
	    adj : length = 1 or 2 : adjustment in x- and y
	
	    cex : character expansion factor (default = 1)
	
	    col : color to use
	
	   font : font for text
	
	_S_i_d_e-_e_f_f_e_c_t_s
	
	     The given text is written onto the current plot.
	
	_S_e_e _A_l_s_o:
	
	     title, text, plot.
	
	_E_x_a_m_p_l_e_s:
	
	     plot(1:10, (-4:5)^2, main="Parabola Points", xlab="xlab")
	     mtext("10 of them")
	     for(s in c(1:2,4))
	         mtext(paste("mtext(..,side=",s,")"), side=s)
	     mtext("mtext(.., line= -2)", line = -2)
	     mtext("mtext(.., line= -1, adj = 0)", line = -1, adj =0)
	     ##--- log axis :
	     plot(1:10, exp(1:10), log='y', main="log='y'", xlab="xlab")
	     for(s in 1:4) mtext(paste("mtext(..,side=",s,")"), side=s)