
\documentclass[border=5pt,multi=true]{standalone}
\usepackage{standalone}
\usepackage{ifthen}
\usepackage{microtype}
\usepackage{lineno}
\usepackage{xspace}
\usepackage{caption}
\usepackage{graphicx}
\usepackage{color}
\usepackage{colortbl}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{amsfonts}
\usepackage{upgreek}
\usepackage{hyperref}
\usepackage{hypcap}
\usepackage{xspace}
\usepackage{upgreek}
\usepackage{cite}
\usepackage{mciteplus}
\usepackage{longtable}



\begin{document}
\DeclareGraphicsExtensions{.pdf}
	\setlength{\unitlength}{\textwidth}
	\centering
	\begin{picture}(0.98,0.32)
		\put(0,0){
	\includegraphics[width=0.42\linewidth]{fig3a}
		}
    		\put(0.30,0.27){(a)}
		\put(0.49,0){
	\includegraphics[width=0.49\linewidth]{fig3b}
		}
    		\put(0.58,0.27){(b)}
	\end{picture}
	
	
\end{document}
