diff --git a/seismic processing/seismic_velocity_depth.m b/seismic processing/seismic_velocity_depth.m
index 799cf30..70e5fe5 100644
--- a/seismic processing/seismic_velocity_depth.m	
+++ b/seismic processing/seismic_velocity_depth.m	
@@ -1,83 +1,6 @@
 % Copyright: 2018 - Teknik Geofisika, Universitas Pertamina
 % URL: https://sites.google.com/site/metkomup/programming
+% Download: https://www.mathworks.com/matlabcentral/fileexchange/66352-mencari-kecepatan-dan-kedalaman-gelombang-seismik-refraksi
 % Cite: Wirantara, Putu Pasek; Nagara, Jeremy Adi Padma; Purwakusuma, Rachenda Pandu; 
 % Rahmah, Tazkia; Christofel, David (2018): Mencari Kecepatan dan Kedalaman Gelombang Seismik Refraksi. figshare.
 % https://doi.org/10.6084/m9.figshare.5946700.v1
-
-clear; close; clc;
-% load data
-data = ReadSegy('Bla-bla.sgy');
-time = [0:500]*0.004;
-
-figure(1)
-for i = 560:700
-    plot(data(:,i)+500*i,time,'m');
-    set(gca,'Ydir','reverse')
-    hold on;
-end
-
-
-axis([280000 330000 0 1.2]);
-ylabel('\bf \fontsize{12}\fontname{Consolas}Time (s)');
-xlabel('\bf \fontsize{12}\fontname{Consolas}Length (m)');
-title('\bf \fontsize{15}\fontname{Consolas}Data Refraksi Seismik');
-
-% first break picking
-[xq,tq] = ginput(4);
-hold on
-plot(xq,tq,'-b')
-
-figure(2)
-plot((xq-280000)/10,tq,'bo');hold on
-plot((xq-280000)/10,tq,'-b');
-ylabel('\bf \fontsize{12}\fontname{Consolas}Time (s)');
-xlabel('\bf \fontsize{12}\fontname{Consolas}Offset (m)');
-title('\bf \fontsize{15}\fontname{Consolas}Data Refraksi Seismik');
-
-
-% calculating velocity
-datapick = [xq tq];
-
-a = datapick;
-figure(1)
-x = a(1:2,1);
-y = a(1:2,2);
-plot(x,y);
-m1 = (y(2)-y(1))/(x(2)-x(1));
-Velocity1 = 1/m1
-
-
-figure(2)
-A = a(2:3,1);
-B = a(2:3,2);
-plot(A,B);
-m2 = (B(2)-B(1))/(A(2)-A(1));
-Velocity2 = 1/m2
-
-figure(3)
-C = a(3:4,1);
-D = a(3:4,2);
-plot(C,D);
-m3 = (D(2)-D(1))/(C(2)-C(1));
-Velocity3 = 1/m3
-
-% Estimating the depth
-n = load('datavelocitydantime.txt');
-x = n(1:3,1);
-y = n(1:3,2);
-
-b = x(1)*y(2)*y(1);
-c = y(2)^2;
-d = y(1)^2;
-e = sqrt(c-d);
-f = 2*e;
-g = y(3)^2;
-h = sqrt(g-d);
-i = y(3)*y(1);
-j = y(3)*y(2);
-k = sqrt(g-c);
-l = 2*(b/f)*h;
-m = 2*k;
-
-D1 = b/f
-D2 = (x(2)-(l/i))*(j/m)+D1
\ No newline at end of file